Young people grow nails at a faster rate. Avoid harsh metal files. File every nail tip from the corner to center but don't file deep into the corners. Leave the cuticle alone . Cutting it invites infection on the nail's tissue.
Short nails are easier to maintain.
Don't torture nails by using them to scrap, pick, scrub, pull or open things . Shake the bottle of polish well or roll between your palms before opening. 2 layers of nail polish is enough on each nail. Too many layers could just turn messy. Avoid painting redos with the help of a foam nail separator .