When you're tempted to nibble at your nails or cuticles, keep your hands busy-and not in your mouth. Doodle on paper, knead a pencil rubber or finger some worry beads.
Give yourself a weekly manicure; the neat appearance may deter you from biting your nails.
Promise yourself a treat if you can grow one nail without biting it.
Paint an anti-biting preparation onto your nails. These are available from chemists, and their bitter taste reminds you to stop nibbling.
If your small child also bites his nails, try giving him a small manicure set - it might encourage him to stop. Make sure you trim his fingernails after each bath-time, and reward the days when he doesn't bite them with a gold star or small treat.