Always check the care label, but one of the best ways to clean a swimsuit is by handwashing it with a mild detergent or a swimsuit cleaner that’s designed to remove chlorine and sunscreen, shares Pennington. If you notice your white bathing suit has yellowed, add a few tablespoons of fabric-brightening baking soda to a sink filled with cool water. Rinse your bathing suit, then line dry. "Never put your swimsuit in the dryer or you’ll risk compromising the stretch and color," adds Bryant.