The proper ratio is 1/2 cup of vinegar to 1 gallon of water. Sponge mops are the best option to wash the floor because they do not cause damage. Cotton mops, often used to wash decks, do not wring out enough water and damage hardwood floors.
Excess water damages the floor, so the proper technique is to remove as much water as possible by wringing the mop regularly. Absorbent cloths are useful for removing any water that pools on the floor. Sponges are good for cleaning limited parts of the floor, and regular wringing of the sponge ensures that the floor gets the right amount of water.