As we age, our tush takes a turn for the worst, and even the plumpest butt can start to droop. While squats are the ultimate cure, you can fake a rounder bum with self-tanner. First apply an all-over base coat to hide stretch marks and bruises. Then go back and give the W-shaped crevice under your bum an extra coat. This will give the illusion of a rounder, perkier derriere. Yes, it's called butt contouring.