Popsugar Beauty Spring Beauty What to Know Before Trying Rainbow Hair Color The Truth About Dyeing Your Hair Rainbow Colors March 15, 2020 by Jessica Cruel View On One Page Photo 6 of 11 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 6 Step 2: Wait In a hair-painting technique, the colorist uses cellophane instead of foil. "Cellophane contains the bleach and prevents it from oxidizing and drying out." Previous Next Start Slideshow Spring BeautyBeauty How-ToHairHair Color