Semi-permanent hair colour is designed to gradually wash out of the hair. In the event that you want the dye to wash out of your hair earlier, special steps will have to be done to speed the dye fade process.
Wash hair with a harsh shampoo, allowing shampoo to sit on hair for 5 minutes before rinsing. Prell is a good brand to use to remove semi-permanent hair dye. Dandruff shampoo is another good choice.
Apply a hot oil treatment to hair. Allow hot oil treatment to sit in hair for 30 minutes.
Wash hair again with Prell, dandruff shampoo or other harsh shampoo and rinse. Repeat.
Wash hair with harsh shampoo everyday for 3 straight days. The semi-permanent hair colour should either be fully removed or mostly removed. If the semi-permanent hair colour remains, the process can be repeated for 3 more days.
Use a hair colour remover designed for the removal of semi-permanent dye if the shampoo method did not work. Hair colour remover can be purchased at professional hair salons.
The more often you wash your hair, the faster the semi-permanent hair dye will fade. Use a good hair conditioner often to prevent dry hair caused by excessive washing.
Black semi-permanent hair dyes can stain hair and may not fade, even with increased hair washing. Hair colour remover does not always work, especially on black dye.