Trim toenails.
Credit: Photograph by Michael Pirrocco

Trim nails with a flat-edged toenail clipper, like one from Ace ($9). To avoid ingrown nails, trim them as short as possible without exposing the skin at the corners of the nail. Nails left too long will bend or crack, and cut into other toes when you're exercising. Use an emery board or a nail file to dull sharp corners.