Abstract: A permanent composition is prepared by aging an aqueous composition comprising a ceramide and cysteine by warming at 30 to 40° C. The ratio of the ceramide to the cysteine may be 1/300 to 1/50 as a ceramide/cysteine ratio (weight ratio). The amount of the ceramide may be 0.01 to 1% by weight, and the amount of cysteine may be 1.5 to 7.5% by weight, relative to the total weight of the permanent composition. The permanent composition may further comprise a phospholipid. The permanent processing is carried out by washing a hair with a shampoo containing the ceramide, applying a treatment containing the ceramide to the hair, applying a mixed composition of the permanent composition and a treatment to the hair, winding the treated hair, and applying the permanent composition to the wound hair.