Wella hair color is a full line of permanent hair coloring that can be used to change your hair color or to cover up gray or white hair. You must mix the actual Wella hair color with Wella hair color developer to activate it before dying your hair. Before doing this, make sure that you’ve used the color swatches that come with Wella hair color kits to identify your natural hair color and the base hair color you’d like to achieve, plus the number of lifts needed to get the tone you want.
Put on old clothing and rubber dishwashing gloves, or other old gloves on to protect your skin and to keep from ruining your clothing. Consider covering the floor and countertop where you’ll be working with old towels, too, in case of spills.
Set out a non-metal bowl to mix the hair color and developer in, plus a clean brush--a paintbrush with no metal in it works well -- to help mix and apply the hair color.
Squeeze one part hair color to two parts developer into the bowl. For every ounce of hair color you add, you’ll add two ounces of developer. This is different than the typical 1 to 1 color-developer ratio seen in other hair coloring products. How much you mix will depend on how much hair you have to color. One ounce of color to two ounces developer is a good touch-up amount or for very short hair; use more for long hair.
Mix the two liquids thoroughly with your brush, then apply to your hair, section by section, right away.
Always do a strand test -- mixing just a small amount, about one cap full of color to two caps full of developer. Use this to color the underside of one small section of your hair. This will help you determine whether you have the right shade of hair color, and how long to process it for, without committing your entire head of hair to the process until you know it will turn out the way you want it.
Don’t use Wella hair coloring on hair that’s been colored with henna or other vegetable dyes or treated with metallic salt dyes.