With a hair colouring brush, apply the mixture on dry, unwashed hair. Start by applying the mixture to the roots, separating the hair strand by strand. Spread the remaining mixture through the rest of the hair. For full head application, cover the entire hair well with the mixture. For touch up application, concentrate solely on the grey or on the root areas. Leave to develop for 30 minutes. After 30 minutes of the development time, wet hair a little and gently lather for 1 minute. Rinse well with water until the water runs clear.