• Proper hygiene and regular inspection of the feet and toes are the first lines of defense against fungal nails.
• Clean and dry feet resist disease.
• Washing the feet with soap and water, remembering to dry thoroughly, is the best way to prevent an infection.
• Shower shoes should be worn when possible in public areas.
• Shoes, socks, or hosiery should be changed more than once daily.
• Toenails should be clipped straight across so that the nail does not extend beyond the tip of the toe.
• Wear shoes that fit well and are made of materials that breathe.
• Avoid wearing excessively tight hosiery, which promote moisture.
• Socks made of synthetic fiber tend to "wick" away moisture faster than cotton or wool socks.
• Disinfect instruments used to cut nails.
• Disinfect home pedicure tools.
• Don't apply polish to nails suspected of infection—those that are red, discolored, or swollen, for example.

Above information supplied by the American Podiatric Medical Association (APMA)