Styling and Finishing

Introduction to Styling and Finishing

Styling and finishing are the final steps in any salon service, where the cut and colour take their definitive form. For the Red Seal exam, this section evaluates your ability to master drying, shaping, straightening, and texturizing techniques, as well as your understanding of the scientific principles behind them. You must not only know how to perform these techniques, but also justify your choices based on hair type, desired result, and safety constraints.

Styling is not limited to aesthetics: it involves precise thermal management (temperatures, exposure times), in-depth knowledge of hair structure (cuticle, cortex, hydrogen and disulfide bonds), and mastery of professional tools. This chapter covers all the theoretical and practical knowledge required by the Interprovincial Standards (Red Seal) Program for the hairstylist trade.

Fundamental Principles of Hair Structure Applied to Styling

The Cuticle and Its Role in Styling

The cuticle is the outer layer of the hair, composed of overlapping scales. Its condition directly determines the quality of the styling:

Intact cuticle (flat scales): smooth, shiny hair that is easy to style. Light reflects uniformly.

Lifted cuticle (open scales): rough, dull hair that absorbs moisture. Styling is more difficult and less durable.

Finishing products (serum, oil, hairspray) work by flattening the cuticle. Heat, if excessive or improperly applied, lifts it irreversibly. The maximum recommended temperature for a hand-held dryer is 60 °C to 70 °C at the nozzle outlet, and 180 °C to 230 °C for a flat iron, depending on hair type.

Chemical Bonds and Temporary Deformation

Thermal and wet styling rely on the breaking and reforming of two types of bonds:

Type of Bond	Strength	Breaking	Reforming	Role in Styling
Hydrogen bond	Weak	Water + heat	Drying + cooling	Temporary shaping (rollers, brushing)
Disulfide bond	Strong	Chemical products (perm, relaxer)	Neutralization	Permanent transformation
Ionic (salt) bond	Medium	pH variation	pH balance	Influences hold and elasticity

> Red Seal key point: Temporary deformation (wet set) only breaks hydrogen bonds. That is why it disappears with humidity. Permanent deformation (perm, relaxer) breaks and reforms disulfide bonds. Never confuse these two mechanisms.

pH and Its Influence on Styling

The pH of hair is between 4.5 and 5.5 (slightly acidic). Styling products must respect this balance:

Acidic pH (3–5): tightens the scales, increases shine, improves hold.

Neutral pH (6–7): has no significant effect on the cuticle.

Alkaline pH (8–10): opens the scales, facilitates product penetration, but weakens the hair.

Hairsprays and fixatives generally have a pH of 5 to 6. Brazilian straightening products (based on formaldehyde or glyoxylic acid) have a pH of 4.5 to 5.5 to avoid damaging the cuticle while allowing the active ingredient to penetrate.

Drying Techniques

Towel Drying and Pre-Drying

Towel drying is the first step. It should remove 70% to 80% of the water contained in the hair. A microfiber towel reduces friction and limits cuticle lifting. Never rub vigorously: pat or wrap instead.

Pre-drying with a hand-held dryer is done at medium temperature (60 °C) and high speed, keeping the nozzle 15 cm to 20 cm from the hair. The goal is to remove excess moisture before precise styling.

Round Brush Drying

Round brush drying is the basic technique for creating volume and curvature. The principles:

29.Section the hair into sections of 2.5 cm to 5 cm (depending on thickness).

30.Tension the section with the brush, placing the brush under the strand for root volume, or above for smoothing.

31.Direct the airflow from roots to ends, following the movement of the brush.

32.Cool each section before releasing it: cooling sets the reformed hydrogen bonds.

The brush diameter determines the degree of curvature:

Brush Diameter	Effect Achieved
20 mm to 30 mm	Tight curls, significant root volume
35 mm to 45 mm	Soft waves, moderate volume
50 mm to 65 mm	Smoothing with slight bend at the ends

Hand-Held Drying (Diffuser)

Hand-held drying, with or without a diffuser, is used for curly or frizzy hair. The diffuser distributes air over a larger surface, reducing the force of the airflow and preserving curl definition.

Temperature: low to medium (50 °C to 60 °C).

Speed: low to medium.

Technique: place the strand in the diffuser, push toward the scalp, hold for 10 to 15 seconds, release. Repeat over the entire head.

> Frequent error: using high speed with a diffuser. This creates a "frizzy" effect and causes loss of curl definition.

Air Drying

Air drying is recommended for very damaged hair or for textured styles. Apply a styling product (mousse, cream) to damp hair, then let it dry without intervention. Drying time depends on thickness and porosity: from 45 minutes (fine hair) to 3 hours (thick hair).

Temporary Shaping Techniques

Wet Setting (Rollers)

Wet setting is a shaping technique on damp or wet hair, using rollers of different diameters. It relies on breaking hydrogen bonds with water, followed by reforming during drying.

Standard procedure:

48.Wash and squeeze out excess water from the hair. Apply a setting lotion (fixative) to damp hair.

49.Section into quadrants: frontal, left parietal, right parietal, occipital.

50.Roll each strand of 2.5 cm to 5 cm width, ensuring uniform tension.

51.Dry under a hooded dryer or air dry until completely dry (residual moisture prevents setting).

52.Allow to cool for 10 to 15 minutes before removing the rollers.

53.Brush and style according to the desired result.

Roller diameter and effect achieved:

Diameter	Effect
15 mm to 20 mm	Very tight curls, "afro" effect
25 mm to 35 mm	Medium curls, pronounced volume
40 mm to 50 mm	Soft waves, natural volume
60 mm and larger	Root volume, almost straight

Curling Iron

The curling iron uses dry heat to temporarily deform the hair. Recommended temperatures:

Hair Type	Recommended Temperature
Fine, damaged, bleached	150 °C to 170 °C
Normal	170 °C to 190 °C
Thick, coarse, resistant	190 °C to 210 °C

Basic technique:

60.Dry the hair completely (damp hair subjected to iron heat undergoes sudden water evaporation, causing internal bubbles and weakening).

61.Section and clip.

62.Take a strand of 2 cm to 3 cm width.

63.Wrap the strand around the barrel, starting 2 cm from the root to avoid scalp burns.

64.Hold for 5 to 10 seconds depending on diameter and temperature.

65.Release and allow to cool before touching the curl.

Flat Iron

The flat iron is used for temporary straightening. It works through direct thermal conduction.

Temperatures: identical to the table above.

Contact time: never exceed 5 seconds per pass on the same section.

Number of passes: maximum 2 to 3 passes per section. Beyond that, the hair undergoes denaturation of keratin (the structural protein of hair).

> Golden rule: if the hair emits a burnt smell or becomes brittle, the temperature is too high or the contact time is too long. Stop immediately and assess the damage.

Permanent and Semi-Permanent Straightening Techniques

Brazilian Straightening (Keratin Treatment)

Brazilian straightening is a semi-permanent treatment that smooths hair for 2 to 4 months. It involves applying a product containing hydrolyzed keratin and a cross-linking agent (formaldehyde or glyoxylic acid).

Procedure:

77.Wash with a clarifying shampoo (sulfate-free) to open the cuticles.

78.Dry to 80% with a dryer.

79.Apply the straightening product in fine sections, brushing to distribute evenly.

80.Leave on for 20 to 30 minutes (according to the manufacturer).

81.Dry completely with a dryer.

82.Flat iron at 210 °C to 230 °C, performing 5 to 8 passes per section.

83.Rinse thoroughly, then apply a neutralizing mask.

84.The client must not wet their hair or tie it up for 48 to 72 hours.

Safety precautions: products containing formaldehyde release toxic vapours. The salon must be ventilated in accordance with occupational health and safety regulations (applicable provincial standards). Wearing gloves and a cartridge mask is mandatory.

Relaxing (Alkaline Chemical Straightening)

Relaxing is a permanent straightening method that breaks disulfide bonds. It uses an alkaline product (sodium hydroxide, guanidine hydroxide, or ammonium thioglycolate).

Product Type	pH	Strength	Use
Sodium hydroxide (lye)	13–14	Very strong	Very curly, resistant hair
Guanidine hydroxide	13–14	Strong	Curly, sensitive hair
Ammonium thioglycolate	9–9.5	Medium	Curly, wavy hair

Procedure:

90.Perform a sensitivity test (patch test) 48 hours beforehand.

91.Protect the scalp with a barrier (petroleum jelly).

92.Apply the product starting at the nape (least porous area) and finishing at the hairline (most porous area).

93.Monitor progress every 2 to 3 minutes by stretching a strand: it should elongate without breaking.

94.Rinse thoroughly with lukewarm water (never hot).

95.Apply the neutralizer (acidic pH) for 5 to 10 minutes.

96.Rinse, then apply a deep conditioning treatment.

> Maximum processing time: 20 minutes for sodium hydroxide, 30 minutes for thioglycolate. Beyond that, the hair literally dissolves.

Finishing Products

Classification of Finishing Products

Product	Primary Function	Form	Application
Hairspray (fixative)	Setting the style	Aerosol or spray	At a distance of 20 cm to 30 cm
Mousse (styling foam)	Volume and hold	Foam	On damp hair
Gel	Strong hold, definition	Gel	On damp or dry hair
Wax	Texturizing, finishing	Wax	On dry hair, small amounts
Serum	Shine, anti-frizz	Oil or silicone	On damp or dry hair
Styling cream	Hydration, flexibility	Cream	On damp hair
Volumizing powder	Root volume	Powder	On roots, dry hair

Hairspray Hold Levels

Hairsprays are classified according to their setting power:

Hold Level	Resin Percentage	Use
Light hold	5% to 10%	Soft styles, natural movement
Medium hold	10% to 15%	Daytime styles, moderate volume
Strong hold	15% to 25%	Structured styles, updos
Extra-strong hold	25% to 40%	Stage styles, extreme fixation

> Red Seal key point: hairspray is applied at a distance to allow uniform evaporation of the solvent (alcohol). Applying too closely creates white deposits and uneven setting.

Product Selection by Hair Type

Hair Type	Recommended Products	Products to Avoid
Fine	Light mousse, light-hold hairspray	Waxes, heavy gels
Thick	Styling cream, serum	Light mousses
Curly	Defining cream, gel	Strong hairsprays
Coloured	Protective serum, alcohol-free products	Products containing sulfates
Damaged	Repairing cream, oil	Products containing alcohol

Advanced Finishing Techniques

The Bun and Updos

The bun is a finishing style that requires mastery of balance and securing.

Principles:

113.Prepare the hair with a texturizing product (volumizing powder or mousse) to increase grip.

114.Create a solid base: the bun must be secured to the scalp, not on the surface.

115.Use bobby pins by inserting them perpendicular to the scalp, then turning them 90°.

116.Distribute the weight of the style: a heavy bun must be supported by multiple anchor points.

Calculating the number of pins: plan for 6 to 8 pins for a medium-sized bun (10 cm diameter), 10 to 12 for a voluminous bun.

Backcombing

Backcombing is a texturizing technique that involves combing hair toward the root to create volume.

Technique: take a strand of 2 cm to 3 cm, hold it perpendicular to the scalp, and comb with a backcombing comb using short movements from mid-length toward the root.

Frequent error: backcombing the entire length. This tangles the ends and makes brushing impossible.

Limit: do not backcomb more than 3 times in the same spot. Beyond that, the hair becomes weakened.

Blowout Smoothing

The blowout is a professional drying technique that combines brushing and airflow.

Procedure:

126.Section into 4 quadrants.

127.Work in sections of 5 cm, starting at the nape.

128.Place the brush under the strand, pull firmly.

129.Direct the airflow perpendicular to the brush, following the gliding movement.

130.Finish each section with a pass of cold air to set.

The total time for a complete blowout is 20 to 40 minutes depending on length and thickness.

Safety and Hygiene

Thermal Management and Burn Prevention

Rinse water temperature must not exceed 38 °C to 40 °C.

Irons must be stored in a heat-resistant stand after use.

Check the temperature of irons on a test strand before application.

Never use an iron on wet hair: the risk of burns and irreversible damage is maximal.

Tool Disinfection

Tool	Disinfection Method	Frequency
Brushes and combs	Immersion in a disinfecting solution (70% alcohol or approved product)	After each client
Irons and dryers	Surface cleaning with a non-corrosive disinfectant	After each client
Pins and clips	Immersion in a disinfecting solution	After each client

> Applicable standard: disinfection requirements are defined by provincial public health regulations. The hairstylist must know the products approved by Health Canada (DIN or NPN).

Ventilation and Chemical Products

Straightening products containing formaldehyde must be used in a ventilated space. The maximum allowable concentration of formaldehyde in the air is 0.1 ppm (parts per million) according to the applicable occupational health and safety regulations. An air extractor or mechanical ventilation is mandatory.

Pitfalls to Avoid

146.Confusing hydrogen and disulfide bonds: wet setting only modifies hydrogen bonds. Any question about the permanence of styling must distinguish these two types of bonds.

147.Neglecting cooling: styling without cooling does not hold. Cooling is as important as heating.

148.Using a single temperature for all hair types: fine and bleached hair requires temperatures 30 °C to 40 °C lower than thick hair.

149.Applying hairspray too closely: the minimum distance is 20 cm. Close application causes white deposits.

150.Forgetting the sensitivity test before relaxing: this test is mandatory 48 hours before the service.

151.Exceeding the relaxer processing time: the maximum time is 20 minutes for sodium hydroxide. Beyond that, the hair dissolves.

152.Backcombing the entire length: backcombing is done only from mid-length toward the root.

153.Drying wet hair with an iron: boiling water creates bubbles in the cortex, irreversibly weakening the hair.

154.Ignoring product pH: a finishing product with an alkaline pH (above 7) lifts the scales and cancels the smoothing effect.

155.Not ventilating during formaldehyde straightening: the maximum allowable concentration is 0.1 ppm. Insufficient ventilation exposes the stylist and client to toxic vapours.

Summary

Styling relies on breaking and reforming hydrogen bonds (temporary) and disulfide bonds (permanent).

The maximum temperature for drying is 60 °C to 70 °C; for irons, 150 °C to 230 °C depending on hair type.

Cooling after heating is essential to set the shape.

Rollers of 15 mm to 20 mm create tight curls; rollers of 60 mm and larger create volume without curvature.

Relaxing with sodium hydroxide has a pH of 13 to 14 and a maximum processing time of 20 minutes.

Brazilian straightening requires adequate ventilation and the wearing of protective equipment.

Hairsprays have a hold of 5% to 40% resin; the application distance is 20 cm to 30 cm.

Tool disinfection after each client is mandatory.

The pH of hair is 4.5 to 5.5; finishing products must respect this balance.

The sensitivity test 48 hours before a relaxer is mandatory.

Self-Assessment Questions (Red Seal Format)

170.What is the maximum recommended temperature for drying fine, damaged hair with a hand-held dryer?

A) 40 °C

B) 60 °C

C) 80 °C

D) 100 °C

175.What type of bond is broken during a wet set?

A) Disulfide bond

B) Hydrogen bond

C) Peptide bond

D) Covalent bond

180.A client has very curly, resistant hair. Which relaxer product is most appropriate?

A) Ammonium thioglycolate at pH 9

B) Sodium hydroxide at pH 13.5

C) Glyoxylic acid at pH 4.5

D) Hydrogen peroxide at pH 3

185.What is the minimum application distance for a setting hairspray?

A) 5 cm

B) 10 cm

C) 20 cm

D) 50 cm

190.What is the maximum processing time for a sodium hydroxide relaxer?

A) 10 minutes

B) 20 minutes

C) 30 minutes

D) 45 minutes

Answers: 1-B, 2-B, 3-B, 4-C, 5-B.

Styling and Finishing