Doing your hair isn't a one-and-done type of thing: It's a continuous process that evolves as the days go by. Day one of your twist-out might be perfectly defined; your blowout might feel like a cloud inside a silk pillowcase. Your style starts to change when day two rolls around — your curls might lose a little bend, and your waves might drop. But when day two turns to day three and day four, that's when things get iffy, and it can be harder to achieve the results you want.