No. Do not apply any products to your hair during the 3 to 4 day development period. Even after that, use caution as many of these products contain alcohol or other ingredients that can strip moisture from the hair and shorten the longevity of your results. Check the labels of your styling products and avoid those containing alcohol and sulfates. Even if your hair has not received a keratin treatment, avoiding the use of these two chemicals is an excellent idea to promote soft, healthy hair.