3. To lend an extra helping hand in the quest for healthy hair, use a hair mask enriched with protein about once a week. Remember, if your hair is super dry, you should leave the cream on longer, and if your hair is oily, you should rinse it out sooner. One we love: Frédéric Fekkai Protein Rx Reparative Treatment Mask, $28.50; available at sephora.com.