Salt
For oily hair, turn to salt for this monthly treatment. Mix two tablespoons of coarse salt with shampoo to create a paste. Apply the mixture to your scalp and scrub vigorously for about a minute. Rinse and apply conditioner. This is the bargain version of Christophe Robin’s uber-luxurious Cleansing Purifying Sea Salt Scrub. The salt targets oil and buildup, and boosts volume. Just don’t use this treatment too often, as overuse will deplete moisture and shine.