I have dark brown hair, can I color it a funky shade of blue?
Lightening dark hair is the most difficult of the color changes. It does the most damage of any of the hair color changes. For this type of service we strongly recommend a professional hairdresser! However, If you are intent on trying it yourself, here is what you can expect. Hair grows 1/2 inch per month (on average) so your dark roots will show in one week and will need a touch-up by two weeks.
Your hair will need to be bleached twice to achieve this color change. The first bleach will leave the hair a nasty shade of orange. The hair must then be dried completely and the second bleach applied. When the hair reaches pale yellow, the bleach must be removed. If you attempt to continue bleaching beyond this point, your hair may melt and break. Some hair is too dark to be bleached successfully before complete breakage occurs. An experienced hairdresser can usually tell this by examining your hair.
When the hair is lifted to a pale yellow, a toner may then be applied achieve a platinum shade (usually a toner with a blue or blue violet base). The scalp may burn and get blisters after two bleach processes. A good hairdresser can avoid this and perhaps would even suggest a color "weave" for you, to lighten your hair without such a root maintenance schedule.