Cosmetology: Colour, Correction and Product Hygiene
What this domain tests
Cosmetology covers make-up, colour theory, face shapes and corrective work, plus nails, hair removal and the chemistry behind the products. The exam expects you to choose products by undertone and texture, adapt a look to the client's features, and keep tools hygienic.
Core rules and concepts
- Undertone (cool, warm, neutral, olive) is separate from surface colour (fair to deep) and from Fitzpatrick phototype. Match foundation to undertone and test on the jawline in daylight.
- Colour wheel: opposite colours neutralise - green cancels redness, peach corrects blue-grey dark circles, yellow brightens purple bruising.
- Face shapes - oval, round, square, heart, long, diamond - guide contouring: recede with darker tones, bring forward with lighter ones.
- Product chemistry: skin pH is about 4.5-5.5, and AHAs or high-pH cleansers shift it. Lash adhesives are cyanoacrylates - patch test 24-48 hours before use and never treat a client who has reacted previously.
- Hygiene: no double-dipping, no shared mascara wands, decant with a spatula onto a palette, clean and disinfect brushes between clients.
Worked example
A client with olive skin and cool undertones wants a "warm golden" foundation for a healthy look. Reasoning: a golden, yellow-based foundation on cool olive skin reads orange at the jawline and oxidises darker within the hour. Test two neutral-cool shades on the jaw, check in daylight, and let them settle for ten minutes before deciding. Warm the face with blush and bronzer rather than the base.
Traps that cost marks
- Testing foundation on the hand or under warm salon lighting.
- Using the same mascara wand on two clients.
- Skipping the patch test for tint, henna or lash adhesive.
- Waxing a client on isotretinoin or within days of a chemical peel.
- Copying a trend look without adapting it to eye shape or skin tone.