Hair masks are typically applied only to the strands, much like conditioners. It is best to avoid applying masks to the scalp as they may contain ingredients or pH levels that are not suitable for it.  If you are wanting to care for you scalp. You can use scalp treatments instead. However, you will want to consider what ingredients you use based on your scalp condition and any sensitivities you might have. We have some recipes in our Luxury Hair Care Formulation Guide.