A method, a kit and a first composition for treating hair are provided. The method for treating hair comprises applying to the hair a first composition comprising in a cosmetically acceptable carrier, one or more linkers, or cosmetically acceptable salts thereof, or mixtures thereof and applying to the hair a second composition comprising in a cosmetically acceptable carrier, one or more electrophile ingredients of Formula I, or cosmetically acceptable salts thereof, or mixtures thereof and wherein the first composition does not comprise any electrophile ingredients of Formula I of the second composition.
