Nails collect dirt and may spread some infections, so keeping them neat and clean is important.
The U.S. Centers for Disease Control and Prevention mentions these suggestions for proper nail hygiene:
Trim nails frequently.
Use soap and water and a nail brush to scrub under the nails when you wash your hands.
Before each use, clean any tools you use to groom your nails; sterilize nail tools when at a public nail salon.
Don’t bite or chew your nails.
Use a clean and sanitized nail clipper to cut a hangnail; never bite or rip it off.