Cosmetology (Cosmetology License) study guide
Cosmetology · Work through your exam, one topic at a time.
A cosmetology license is the state-issued credential that legally authorizes you to perform hair, skin, and nail services for paying clients. It is required in every U.S. The Cosmetology study guide has 10 sections and about 3,199 words.
01Sanitation, Disinfection, and Client Safety
Cleaning uses soap or detergent and water to remove visible dirt and debris; it does not kill pathogens. Disinfection uses an EPA-registered hospital-grade chemical to destroy most bacteria, fungi, and viruses on nonporous surfaces.
340 words, about 2 min02Haircutting and Hair Shaping
Reference points guide consistent sectioning: the apex (highest point of the head), parietal ridge , occipital bone , four corners , and nape . Cutting lines are horizontal, vertical, or diagonal; sectioning follows those lines to keep lengths balanced.
319 words, about 2 min03Hair Coloring and Lightening
Natural hair levels run 1 (black) to 10 (lightest blonde) , with undertone describing the warmth beneath the surface. Primary colors are blue, red, and yellow; secondary colors (green, orange, violet) are mixes of two primaries.
322 words, about 2 min04Hairstyling and Finishing
Wet styling (rollers, pin curls, air forming) sets hair through hydrogen bonds and requires the hair to dry completely before it is disturbed. Thermal styling (blow dryer, curling iron, flat iron) temporarily reshapes hair with heat; the set lasts until moisture or heat resets it.
330 words, about 2 min05Chemical Texture Services (Permanent Waving and Relaxing)
Both perming and relaxing work on disulfide bonds in the cortex. A reducing agent breaks those bonds; an oxidizing agent (neutralizer) rebuilds them in the new shape.
311 words, about 2 min06Shampooing, Conditioning, and Scalp Care
Hair and scalp sit at a mildly acidic pH (roughly 4.5–5.5 ). Alkaline shampoos swell the cuticle and clean aggressively; acidic and balanced shampoos help the cuticle lie flat and preserve color.
303 words, about 2 min07Skin Care and Facial Services
Every facial begins with skin analysis : observe pore size, oiliness, texture, and sensitivity, and ask about allergies, medications, and recent cosmetic procedures. Basic skin types are normal, dry, oily, and combination ; conditions such as dehydration, sensitivity, and acne are layered on top.
296 words, about 1 min08Nail Care and Manicuring
The nail plate is the hard, non-living keratin surface. Beneath it lies the nail bed .
333 words, about 2 min09Anatomy, Physiology, and Disorders of Hair and Skin
The hair shaft has three layers: the cuticle (outer overlapping scales), the cortex (the thick middle layer holding melanin, where chemical and physical changes occur), and the medulla (the innermost core, sometimes absent in fine hair). The root sits in the follicle ; its bulb covers the papilla , which supplies blood and nutrients.
330 words, about 2 min10Salon Business, Professional Ethics, and State Regulations
Common ownership forms are sole proprietorship (one owner, unlimited liability), partnership , corporation (including S-corporation), and limited liability company . Compensation models include commission , salary , hourly , and booth rental , where the stylist rents space, sets their own prices, and is generally an independent contractor responsible for their own taxes and insurance.
315 words, about 2 min