Esthetician (Esthetician License) cheat sheet

Epidermal layers, deep to superficial: stratum basale (germinativum) → spinosum → granulosum → lucidum (palms and soles only) → corneum.

Keratinocytes are produced in the stratum basale and migrate upward; turnover from basal layer to shedding takes about 28 days.

Dermis layers: papillary (thin, upper, loose areolar tissue) and reticular (thick, dense irregular collagen and elastin).

Melanocytes in the stratum basale make melanin using the enzyme tyrosinase and transfer it to keratinocytes in melanosomes; melanin absorbs UV.

Langerhans cells are the epidermis's immune (phagocytic) cells; Merkel cells are sensory receptors for light touch.

Sebaceous glands secrete sebum and attach to hair follicles; eccrine glands occur over most of the body, apocrine glands in axillae and groin.

Skin surface pH is about 4.5–5.5 (acid mantle); the barrier function resides in the intercellular lipids of the stratum corneum.

UVA reaches the dermis and drives photoaging; UVB is shorter, burns the epidermis, and triggers vitamin D synthesis.

Skin functions: protection, sensation, thermoregulation, excretion, secretion, absorption, and vitamin D synthesis.

Primary lesions: macule, papule, pustule, vesicle, bulla, nodule, wheal, cyst. Secondary lesions: crust, scale, scar, fissure, ulcer, excoriation.

Open comedo = oxidized plug at the follicle opening (blackhead); closed comedo = plug below the surface (whitehead).

Contagious conditions are absolute contraindications: herpes simplex, verruca (HPV), impetigo, ringworm, conjunctivitis, and active cold sores.

Rosacea shows chronic flushing, telangiectasia, and papules; avoid heat, steam, strong exfoliation, alcohol, and spicy-food triggers.

Melasma is hormonally and UV-driven facial hyperpigmentation; post-inflammatory hyperpigmentation follows injury or inflammation and darkens with UV exposure.

Seborrheic dermatitis is associated with Malassezia yeast and appears as oily, yellowish scales on scalp, brows, and nasolabial folds.

Basal cell carcinoma is the most common skin cancer (pearly, sun-exposed skin); melanoma is screened with the ABCDE rule (asymmetry, border, color, diameter, evolving).

Vitiligo is autoimmune melanocyte destruction producing depigmented patches; it is not contagious and is outside esthetic treatment scope.

Fitzpatrick type I always burns and never tans; type VI never burns and tans deeply.

Consultation sequence: intake and health history → medications and allergies → informed consent → skin analysis → treatment plan → home care and rebooking.

Skin type is genetic oil production (normal, dry, oily, combination); skin condition is changeable (dehydration, sensitivity, hyperpigmentation, acne).

Fitzpatrick I–VI predicts UV response and guides peel depth, device settings, and PIH risk; types IV–VI carry the highest PIH risk.

Wood's lamp readings: yellow-green = oily; violet = dehydrated; brown = hyperpigmentation; coral-pink = acne bacteria; white = dead surface cells; blue-white = normal.

Magnifying lamp or loupe is used to grade pore size, texture, sebum, and vascularity during analysis.

Treatment intervals of about 4 weeks align with the roughly 28-day epidermal turnover cycle.

Patch test 24–48 hours before a first-time product or chemical service for clients with known sensitivity.

A treatment plan documents goals, modalities, expected downtime, contraindications, and referral to a physician when disease is suspected.

Sanitation removes visible debris and lowers microbial counts; disinfection kills most pathogens except spores; sterilization destroys all organisms including spores.

Use an EPA-registered hospital-grade disinfectant at label dilution in a labeled, covered container, with full immersion for the label contact time (commonly 10 minutes).

Autoclave sterilization: about 250°F at 15 psi for 15–20 minutes; not suitable for plastics, electronics, or heat-sensitive items.

Ultrasonic cleaners only clean; they must be followed by disinfection or sterilization.

OSHA bloodborne pathogen rules cover HBV, HCV, and HIV; standard (universal) precautions treat all blood and body fluids as infectious.

Wash hands at least 20 seconds before and after gloves, after restroom use, and after contact with body fluids.

Porous single-use items (sponges, cotton, wooden applicators, tissue) are discarded after one client; never double-dip into product.

Soiled linens go into a closed receptacle and are laundered; clean and dirty items are stored physically separate.

Verify disinfectant dilution with test strips and change solutions per manufacturer instructions, typically daily.

Facial sequence: consult → cleanse → analyze → exfoliate → extractions → massage → mask → tone → moisturize → SPF.

Cleanser selection: gel or foaming for oily and combination skin, cream or oil for dry and mature skin, micellar for sensitive skin or quick removal.

AHAs (glycolic, lactic, malic, tartaric) are water-soluble and act on the epidermis; BHA (salicylic acid) is oil-soluble and works inside the follicle.

Glycolic acid has the smallest AHA molecule and therefore the deepest penetration of the AHAs; all AHAs increase photosensitivity.

Salicylic acid is aspirin-related; avoid with aspirin allergy and do not use on clients taking isotretinoin.

Extractions follow steaming or warm compresses to soften sebum; never extract inflamed, cystic, or pustular lesions.

Mask choice: clay/absorbent for oily skin, gel/hydrating for dry or dehydrated skin, enzyme for gentle exfoliation, paraffin for mature dry skin.

Steam: 3–5 minutes at 8–10 inches from the face; contraindicated for rosacea, recent chemical peels, and steam-sensitive respiratory clients.

Toners restore the acid mantle after cleansing; avoid high-alcohol formulas on dry or sensitive skin.

Effleurage: light, continuous gliding with the palms, applied upward and outward; it opens and closes the massage.

Petrissage: kneading, lifting, and squeezing of muscle tissue; deeper pressure than effleurage.

Tapotement: percussion (hacking, tapping, cupping) used briefly to stimulate circulation and nerve endings.

Friction: small circular or cross-fiber movements that warm tissue and break down adhesions; includes chucking and rolling.

Vibration (shaking): rapid trembling used to stimulate nerves and relax muscle.

Direction rule: strokes follow muscle direction and drain toward lymph nodes; facial massage moves upward and outward.

Massage contraindications: fever, contagious illness, recent surgery, acute inflammation, bruising, thrombosis, and uncontrolled hypertension.

Lubricant choice: more oil or cream for dry or mature skin, minimal or none for oily and acne-prone skin.

Hair growth cycle: anagen (active growth, hair best anchored for waxing) → catagen (transition) → telogen (resting, hair sheds).

Apply wax in the direction of hair growth and remove it against the growth while holding the skin taut.

Hard wax is stripless and low-temperature, suited to the face, underarms, and bikini; soft wax requires a removal strip.

Test wax temperature on the inner wrist before applying it to the face.

Do not wax clients using isotretinoin within 6–12 months, on retinoid- or AHA-treated areas, within 7–14 days of a peel, or over varicose veins, moles, and inflamed skin.

Aftercare: no sun, heat, friction, swimming, or fragranced products for 24–48 hours; gentle exfoliation begins 48 hours later to prevent ingrown hairs.

Sugaring paste (sugar, lemon juice, water) is water-soluble, applied against the hair growth and removed with the growth; it adheres to hair rather than live skin.

Depilatories dissolve hair with thioglycolates or barium sulfide; always patch test and never apply to irritated or broken skin.

Post-wax folliculitis appears as red papules and pustules around follicles; it contraindicates further waxing and requires referral if spreading.

Primary pigment colors: red, yellow, blue. Secondary colors: orange, green, violet.

Complementary pairs neutralize: green cancels red (redness), violet cancels yellow, peach or orange cancels blue (under-eye circles).

Warm undertones (yellow, peach) suit gold, coral, and warm browns; cool undertones (pink, blue) suit silver, rose, and blue-based shades.

Color schemes: monochromatic (one hue), analogous (adjacent hues), complementary (opposite hues), triadic (three evenly spaced hues).

Dark shades recede and light shades advance; use this to contour and highlight face shape.

Match foundation along the jawline in natural daylight; test the three shades closest to the client's skin.

Makeup sanitation: sharpen pencils, wash brushes after each client, use disposable wands, never double-dip, and scrape product onto a palette.

Watts = volts × amps. Volt measures electrical pressure, amp measures current flow, ohm measures resistance, watt measures power.

Direct current (DC) flows one direction; alternating current (AC) changes direction; galvanic current is constant DC used for iontophoresis and desincrustation.

Cataphoresis uses the positive pole (acidic reaction, closes pores); anaphoresis uses the negative pole (alkaline reaction, softens sebum).

High-frequency (Tesla) current is alternating current producing violet light and ozone; used for acne and to stimulate circulation.

Water and metals conduct electricity; rubber, glass, and dry wood insulate.

pH scale 0–14: below 7 acidic, 7 neutral, above 7 alkaline; skin averages 4.5–5.5. Alkaline products swell hair and soften keratin.

Emulsion = oil + water + emulsifier; oil-in-water formulas are lighter and rinse with water, water-in-oil formulas are heavier and water-resistant.

Humectants bind water (glycerin, hyaluronic acid); emollients soften and smooth (oils, esters); occlusives block water loss (petrolatum, dimethicone).

Antioxidants (vitamins A, C, E) neutralize free radicals; preservatives prevent microbial growth in water-containing products.

Peel depth: superficial (epidermis to papillary dermis), medium (papillary to upper reticular dermis), deep (reticular dermis); deep peels are physician-level.

Glycolic acid peels are neutralized with sodium hydroxide or sodium bicarbonate; TCA peels self-neutralize.

Contraindications for peels and microdermabrasion: isotretinoin within 6–12 months, pregnancy, active infection or cold sores, recent waxing, photosensitizing medications, and a compromised barrier.

Fitzpatrick IV–VI carry higher post-inflammatory hyperpigmentation risk; pretreat, use conservative settings, and require daily broad-spectrum SPF.

Microdermabrasion uses crystal or diamond-tip abrasion with vacuum suction; avoid telangiectasia, rosacea, active acne, and bony areas.

LED: blue (~415 nm) targets acne bacteria; red (~633 nm) supports collagen and reduces inflammation.

Ultrasound at about 1 MHz produces microstreaming and heat; avoid over the eyes, thyroid, heart, and pregnant abdomen.

Post-treatment protocol: broad-spectrum SPF and no heat, exercise, or strong actives for 24–48 hours; no waxing or exfoliation for at least a week.

Scope of practice: estheticians provide cosmetic services and cannot diagnose disease, prescribe medication, or perform medical procedures.

Federal roles: FDA regulates cosmetic labeling and safety, OSHA protects worker safety, and the EPA registers disinfectants.

State boards license estheticians and set sanitation rules, continuing education hours, and enforcement; requirements vary by state.

Informed consent and confidential client records must be maintained; records include intake, contraindications, products used, and outcomes.

Ethical duties: no false or misleading claims, no guaranteed results, respect professional boundaries, and refer medical conditions to a physician.

Advertising and before/after images require client consent, and testimonials must be truthful.

Compensation models include hourly, commission, salary, and booth rent; product cost is commonly targeted at 10–15% of service revenue.

Safety Data Sheets (SDS) for all products must be accessible in the workplace.