WA Cosmetology common mistakes
WA Cosmetology · Understand the traps and how to avoid them.
Choosing a sanitizer wipe as the final step before reusing a nonporous implement on another client, instead of using an EPA-registered hospital disinfectant for the labeled contact time.
Candidates memorize the words 'clean, sanitize, disinfect' but blur which step is required for implements that touch skin or blood; exam items test the distinction directly.
What to do instead
Make a three-column chart of clean vs sanitize vs disinfect and write the required contact time and example product for each; practice classifying 20 implements and surfaces aloud.
Pouring disinfectant into a jar by eye until it 'looks strong enough' and pulling implements out before the labeled immersion time has elapsed.
Dilution and contact time are easy to skim on labels, and candidates often rely on color or smell rather than measurement and a timer.
What to do instead
Memorize the rule: read the label, measure with a cup, submerge completely, set a timer for the full contact time, and never top off an old solution.
During a relaxer touch-up, applying product over the previously relaxed hair because the new growth is difficult to isolate.
Candidates focus on getting a smooth result and underestimate how overlap causes chemical burns, breakage, and scalp irritation.
What to do instead
Practice parting and isolating new growth only, apply protective base to the scalp, and state the rule: relaxer goes on new growth, never on previously relaxed hair.
Using 20-volume developer for every color formula or swapping developer volumes without matching the desired lift or deposit.
Developer volumes look interchangeable on a shelf, and candidates memorize '20 volume' as a default instead of linking volume to lift and deposit.
What to do instead
Build a flashcard set for 10, 20, 30, and 40 volume that names the lift/deposit result and one example use; check the manufacturer's mixing ratio before answering.
Cutting a blunt or one-length line without first establishing a stationary guideline, then using inconsistent elevation through the section.
Candidates rush to cut and rely on the first cut as a guide without checking whether it is level and whether the hair is held at the same angle throughout.
What to do instead
Practice the sequence: section, establish a stationary guide, cut to the guide, and cross-check elevation before moving to the next subsection.
Detangling wet hair by combing from the scalp straight to the ends instead of starting at the ends and working upward.
Wet hair stretches and breaks easily, but candidates treat detangling as a quick step and copy the motion they use on dry hair.
What to do instead
Use a wide-tooth comb, start at the ends, and work upward in small sections while supporting the hair; state the reason: wet hair is weaker and must be detangled gently.
Waxing a client who reports current isotretinoin/Accutane use or recent retinoid use because the skin appears normal.
Candidates rely on visual inspection and skip the client intake, missing that these medications thin the skin and make waxing a contraindication.
What to do instead
Memorize a short contraindication list for waxing, including isotretinoin, recent retinoids, sunburn, open lesions, and recent exfoliation; always complete an intake form before waxing.
Double-dipping the wax applicator after it has touched the client's skin back into the main wax pot.
Candidates treat wax as self-cleaning because it is hot, and they focus on speed rather than cross-contamination.
What to do instead
Use single-use applicators or a two-pot method; never return a used applicator to the main wax supply, and state the contamination risk aloud when practicing.
Using a coarse electric file bit on the natural nail plate and moving the bit back and forth across the nail.
Candidates confuse product reduction with nail preparation and assume a coarser bit works faster without damaging the natural nail.
What to do instead
Use a fine bit at low speed, file in one direction, and keep the bit off the natural nail plate; memorize the rule that natural nails are thinned, not drilled.
Skipping hand washing and relying on gloves as a substitute for hand hygiene between clients.
Gloves create a barrier, so candidates assume hands are protected and clean, but gloves can tear and do not replace hand washing.
What to do instead
Practice the sequence: wash hands, dry, put on gloves; remove gloves, wash hands again. State that gloves are changed between clients and are never a hand-hygiene substitute.