What It Is An overnight treatment to help reverse the appearance of damaged hair – for swingy, silky (de-stressed) strands by A.M. How to Use Apply on dry hair once or twice a week. For deep nourishment, leave on overnight – and then wash out with your favorite Bb.Shampoo and Conditioner. After cleansing, use Save the Day Daytime Damage Repair Fluid for around-the-clock repair.