Abstract: The present disclosure relates to a method for styling mammalian hair fibers, including providing body, straightening, relaxing, curling, or applying any other desired modification to the shape of the hair. The method comprises applying a hair styling composition comprising at least one hair-penetrating phenol-based monomer to the hair, allowing the monomers to penetrate within the hair and curing such monomers to internally form a polymer able to overcome the tendency of the hair to revert to its native shape. When curing is performed while the hair is in a desired modified shape, the resulting polymers may maintain the modified shape. Suitable compositions and kits allowing to prepare the same are also disclosed.