You are applying a toning product immediately at the roots, rubbing it in, and then allowing the lather to soak through to the ends so that the majority of the product is on the bases. While the lather will keep your limitations in check, most of the pigments will get to work where they're needed the most. The product should be applied to dry hair as needed, left on for as long as is necessary to set in, and then shampooed out with water if you have brassiness all over your hair.