The best way to clean a hardwood floor is to make sure that you don't use excessive moisture. For the actual process, you should just get a dry mop. You should try to make sure that your hardwood floor never gets wet at all. In the event that someone steps on your floor with their muddy shoes, damp mopping is the way to go about dealing with that. Even if it looks messy, it is better not to douse the floor; the moisture seeps between the cracks in the boards and gets underneath it, doing damage to the floors. The best way to go is to do it often and to keep it dry.