It's one of life's little ironies that wearing a lot of nail polish, particularly in darker colors, can lead to badly stained fingernails, leaving you no choice but to continue coloring your nails, even when what you're really dying to try is a sleek and low-maintenance au naturel style. The easiest and healthiest way to reclaim pretty pink nails is with a lemon. Slice one in half and wiggle your finger into the center -- the natural acids soften and whiten. Give it a few seconds and then repeat for each of your other nails.