Salt-and-Oil Treatment Sea salt enhances and defines natural waves, while fragrant essential oil helps lock in moisture and softness. Mix 2 teaspoons fine sea salt, 1 cup warm water, and 4 to 5 drops essential oil (such as grapefruit) in a reusable spray bottle. Shake well to dissolve salt and spray. Run your fingers through to distribute, twisting sections of hair into ropes to further define waves. Let dry naturally, then run fingers through again to create loose, irregular ringlets.