If you want to dye hair to a much lighter shade than your current color, you must bleach it first. Bleaching your hair will remove the color from the shaft, giving you a blank canvas with which to work. Once you've bleached the hair, you can dye it any color you want -- from platinum blond to auburn to hot pink or blue.
Put on a pair of gloves. Typically, bleaching kits come with a pair of plastic gloves to protect your hands from the possibility of burns.
Put on protective clothing to prevent bleaching your good clothes. Wear old clothing or tie an old towel around your neck.
Add 3 tbsp. of the hydrogen peroxide provided in the bleaching kit to the powder bleach in the bowl, also provided with the kit. Stir the peroxide and bleach together using the provided brush until the mixture is about the same consistency as icing -- not too thick, but not too runny.
Dip the brush into the bleach mixture to coat the bristles. Brush the bleach onto your hair starting with a section in the front of your hair and moving back. Coat your entire head of hair with the bleach.
Place a plastic cap over your head, and allow your hair to set for the time specified in the instructions. Some instructions may tell you to apply the heat from a hair dryer onto your head. Never leave the bleach in your hair for longer than the time specified, as this can result in hair breakage, damage and even hair loss.
Rinse the bleach from your hair then wash it using a mild shampoo.
Condition your hair using regular conditioner or a deep conditioner to prevent your hair from over-drying. Allow your hair to air dry, then dye it as you normally would.