Article: Nails grow about 1/10 of an inch (2.5 mm) every month, meaning that it takes 3-6 to grow a full nail. If you cut your nails frequentlysay, once each week or twoyou won't need to worry about them growing too long or too wild. If your nails begin to hurt at the edges, you might be developing an ingrown nail; try to trim away the painful growth before it goes too deep, but it would be wiser to seek a health care professional. The goal here is to remove the "free edges" of your nails: the opaque, off-white crescents that grow at the tips of your nails. Cut the nails almost completely straight across, and round them a little at the corners to keep the nails strong. Cutting the nail straight will reduce your chance of developing ingrown nails. If you are a finger-style guitarist, consider leaving the nails long on your picking hand. Keep at least 1/16th inch (1.5 to 2 mm) of nail on each finger of your picking hand. It can be tempting to keep on trimming your nails (for the sake of convenience, aesthetic, or compulsion) even after you've removed the "free edge". If you trim too deeply, however, you will expose the sensitive skin beneath the nail, and you may increase your risk of infection. Try to keep the ends of your nails even with the top of your finger or remove all but a tiny sliver of the opaque "free edge".

What is a summary?
Trim your nails often, but do not be overzealous. Cut your fingernails. Be careful not to cut too much.