Step 1: Color Remover
The first thing you should do to lighten dark hair, is get as much black (or dark color) out of your hair as you can. You may have to do this process a few times. Color remover, like “Color Oops,” works by entering the hair shaft and removing the artificial color molecules. It does not remove any of the natural pigment in your hair. Because of this, this step will not work on hair that has not been previously colored.
Color remover will not return your hair to the same color it was before dying it.
The end result of using color remover is going to be a brassy color. You can tone this color and live with a more desirable tone of hair for a few weeks. Since the color remover may cause some damage, spend time reconditioning your hair.