Nails should be kept fairly short. The longer they are, the more easily they are damaged – especially your fingernails, if you work with your hands. If they are fine, you can use a normal clipper; for anything thicker – usually toenails, but sometimes fingernails – you will need a heavy-duty version. Use a nail file for shaping, or if it hurts when you clip your nails. You don’t need to use it in...