The full instructions and tips are included in the packet. The following is an overview:
Mixing: You can either mix the powder with warm water and apply to your hair or you can mix the powders with some acidic fruit juice such as lemon juice and leave to soak for 8 to 12 hours.
Application: Divide your hair into sections and apply the paste to each section. It should be fully coated from the roots to the ends. Put plenty on. When your hair is completely coated with the paste, cover your hair with the shower cap included in the packet. Clean any leftover paste off your skin (such as on your face and the nape of your neck).
Leave the paste on your hair for 30 to 120 minutes. The longer you leave it to develop, the stronger the colour will be. Rinse out your hair until the water runs clear. Use a little shampoo if you would like, then rinse and condition as usual.