MT Cosmetology cheat sheet

Hair is roughly 90% keratin protein by weight; the cortex supplies strength and elasticity, the cuticle is the outer protective scale layer, and the medulla is the often-absent central core.

Wet hair stretches up to about 50% of its length before breaking, while dry hair stretches only about 20%; this is why wet-setting and wet-cutting are possible but also why wet hair is more fragile.

The three growth stages are anagen (active growth, roughly 2-7 years), catagen (transition, a few weeks), and telogen (resting/shedding, roughly 3 months).

A cowlick is a growth pattern in which hair stands up or grows in opposing directions; a whorl is a circular growth pattern, most often at the crown.

The four basic haircut forms are solid (one-length), graduated, layered, and uniformly layered; each is defined by elevation and the resulting weight distribution.

Elevation of 0 degrees produces a solid form; 45 degrees produces graduation; 90 degrees produces uniform layers; beyond 90 degrees produces increased layering.

Guideline types: stationary (one fixed section used throughout), traveling (moves with each section), and section (a new guideline cut for each subsection).

Texturizing includes point cutting, notching, slicing, and thinning shears; all reduce weight or soften ends and should be used sparingly on fine hair.

A razor cut creates softer, tapered ends and is best on medium to coarse hair; on fine or curly hair it can cause frizz and unevenness.

The hair color wheel places primary colors red, yellow, and blue opposite their secondary complements green, violet, and orange; complementary colors neutralize each other's tone.

The universal color level scale runs from level 1 (black) to level 10 (lightest blonde); level is depth, while tone is the warm, neutral, or cool character of the color.

Developer (hydrogen peroxide) volume determines lift: 10 volume (3%) deposits only, 20 volume (6%) lifts 1-2 levels, 30 volume (9%) lifts 2-3 levels, and 40 volume (12%) lifts 3-4 levels.

Underlying pigment is the warm color remaining after melanin is removed; it darkens as level decreases (yellow at 8-10, gold at 6-7, orange at 4-5, red at 2-3, dark red at 1).

A patch test checks for allergic reaction to dye; a strand test checks processing time, color result, and hair condition before full application.

The relaxer strength is chosen by hair texture and resistance, not by scalp sensitivity; base relaxers use sodium hydroxide, no-base relaxers use lithium or guanidine hydroxide and require a protective base.

Relaxer processing is timed from the last application, and the relaxer must be completely rinsed before the neutralizer (shampoo at the hair's natural pH) is applied to stop the chemical action.

A permanent wave reduces disulfide bonds with thioglycolate, reshapes them on rods, then rebuilds them with neutralizer (usually hydrogen peroxide or sodium bromate).

The chemical texture decision rule: never relax hair that has been bleached or highlighted without a strand test, and wait at least two weeks between a relaxer and a color service unless the product line specifies otherwise.

The five basic wet styling tools are the roller, the thermal iron, the blow dryer with brush, finger waving, and pin curls; each sets hair by temporarily breaking and reforming hydrogen bonds.

Pin curls: a stem (straight section from scalp) controls direction and mobility, and a circle (the curled portion) controls the size of the wave; a ridge curl is used at the hairline.

Finger waving uses alternating ridge and hollow waves with the index and middle fingers; the finished wave must be smooth, even, and follow the natural growth pattern.

Thermal iron temperature rule of thumb: about 250-310 F for fine or damaged hair, 310-360 F for medium hair, and 360-410 F for coarse, resistant hair; always test on a small section.

Blow-drying with a round brush adds volume and direction; a paddle brush smooths; a vent brush speeds drying; direct airflow down the hair shaft smooths the cuticle.

Backcombing (teasing) and backbrushing add volume at the scalp but damage the cuticle; they should be used lightly and removed gently with a wide-tooth comb.

Finishing products: mousse adds volume and control, gel gives firm hold, pomade adds shine and weight, and hairspray is the final setting layer.

A French braid interlaces three strands while adding hair from each side; a fishtail braid uses two sections with small crossing strands and is a finishing, not a volume, technique.

Skin types are normal, dry, oily, combination, and sensitive; skin conditions (dehydration, acne, couperose) are treated differently from skin types and may require referral.

The basic facial sequence is consultation and skin analysis, cleansing, exfoliation, massage, extraction if indicated, mask, toner, moisturizer, and sun protection.

Facial massage movements include effleurage (light gliding), petrissage (kneading), tapotement (tapping), and friction; all are performed upward and outward following muscle direction.

Extraction is limited to visible comedones and pustules that are ready; deep cystic lesions, inflamed acne, and suspicious growths must be referred to a physician.

Contraindications for facial services include open lesions, sunburn, recent chemical peels, active herpes, and known product allergies.

The Fitzpatrick scale classifies skin types I-VI by response to sun exposure and guides waxing, exfoliation, and light-based service decisions.

Waxing: hair should be at least 1/4 inch long, the wax is applied in the direction of hair growth and removed against it, and the skin is held taut to minimize trauma.

Makeup color theory: complementary colors neutralize (green cancels redness, peach cancels blue), and undertone (warm, cool, neutral) drives foundation selection.

Nail anatomy: the nail plate is the visible hard keratin structure, the nail bed is the skin beneath it, the matrix produces new nail cells, and the lunula is the visible whitish half-moon at the base.

The cuticle (eponychium) is living tissue at the base of the nail plate; it should be softened and pushed back gently, never cut, in a standard manicure.

The free edge is the portion of the nail plate extending beyond the fingertip; the hyponychium is the seal under the free edge that protects against infection.

Nail shapes include square, squoval, round, oval, and pointed; shape is chosen by natural nail form, lifestyle, and service type.

The basic manicure sequence is sanitize hands, shape nails, soak, push cuticle, trim only hangnails, massage, base coat, polish, and top coat.

A pedicure follows the same logic with additional attention to callus reduction; tools must be disinfected between clients and single-use items discarded.

Nail disorders: onychomycosis is a fungal infection (refer), paronychia is inflammation of the tissue around the nail (refer), and onychorrhexis is brittleness with ridges.

Nail services are contraindicated on inflamed, infected, or broken skin around the nail; the service should be refused and the client referred.

The integumentary system consists of skin, hair, nails, and glands; its functions are protection, sensation, heat regulation, excretion, secretion, and absorption.

Skin layers: epidermis (outer, avascular), dermis (contains nerves, blood vessels, glands, and hair follicles), and subcutaneous (fat and connective tissue).

The hair follicle is a tube in the dermis; the papilla at its base supplies blood and nutrients, and the arrector pili muscle causes goose bumps.

The sebaceous gland secretes sebum, which lubricates skin and hair; the sudoriferous (sweat) gland regulates temperature.

Bones of the skull and face relevant to cosmetology include the frontal, parietal, occipital, temporal, zygomatic, maxilla, and mandible.

Muscles of facial expression include the frontalis, orbicularis oculi, orbicularis oris, zygomaticus, mentalis, and platysma; massage follows their fiber direction.

Nerves of the face and scalp include the trifacial (trigeminal) and facial nerves; the supraorbital, infraorbital, and mental nerves are pressure points.

Blood supply to the head and neck comes from the common carotid artery, which branches into the internal and external carotid; the external carotid supplies the face and scalp.

Histology of hair: the cuticle has overlapping scales, the cortex contains melanin and the disulfide bonds that give shape, and the medulla is a hollow core present mainly in thick hair.

Levels of control: sanitation reduces pathogens on surfaces, disinfection destroys most pathogens on implements, and sterilization destroys all microbial life including spores.

An EPA-registered hospital-grade disinfectant with a tuberculocidal claim is the standard for implements in cosmetology; follow the label's contact time exactly.

Implements must be cleaned of debris before disinfection; organic matter inactivates disinfectants, so washing and drying precede immersion.

Porous items (nail files, buffers, wooden sticks, cotton, sponges) cannot be reliably disinfected and must be discarded after single use.

Blood and body fluid spills require gloves and an EPA-registered disinfectant effective against HIV and hepatitis; contaminated waste goes in a closed container.

Hand washing with soap and warm water for at least 20 seconds is the single most effective infection control measure; hand sanitizer is not a substitute when hands are soiled.

A disinfectant container must be labeled, covered, and changed according to the manufacturer's instructions; test strips or a log verify concentration.

A client with a known communicable disease, open lesion, or parasite infestation must be refused service and referred to a physician.

Pathogens: bacteria (Staphylococcus, Streptococcus), fungi (tinea), viruses (hepatitis B, HIV), and parasites (lice, scabies); each requires a different level of control.

The Montana Board of Barbers and Cosmetologists regulates licensing of cosmetologists, barbers, manicurists, estheticians, electrologists, and salons under the Montana Department of Labor and Industry.

Licensure requires completion of an approved program (commonly 1,500 hours for cosmetology in Montana), passage of the state written and practical exams, and payment of fees.

A license must be displayed in the salon; a licensee must report a change of name or address to the board within the timeframe stated in the rules.

Salon licensure requires inspection and compliance with sanitation, equipment, and facility rules; a salon may not operate without a current license.

Continuing education requirements, if applicable, must be completed and documented before renewal; renewal cycles and fees are set by board rule.

Scope of practice: a licensee may perform only services within the licensed scope; medical procedures such as diagnosing skin disease or treating infection are outside the scope.

Professional ethics include confidentiality of client information, informed consent before chemical services, honest disclosure of pricing, and refusing unsafe services.

Sanitation and safety violations are grounds for disciplinary action, including fines, suspension, or revocation of license by the board.