Dark hardwoods come from a variety of woods including cypress, hickory and walnut, just to name a few. Before cleaning your dark hardwood floor, determine if your floors are finished, waxed or natural. Once you know this, clean your floors the proper way without damaging the wood or finish.
The main problem with all dark hardwood floors (finished, waxed and natural) is that they tend to show dust and dirt more than lighter floors. They need regular dusting, sometimes two or three times a week. Take a dust mop and mop the wood floors. Do not use furniture polish or dust spray, as that will make your floors slippery and dangerous. In fact, for your regular dusting, don't use anything on your mop; a good mop will pick up the dust. Shake it outside when you're done.
You can use a mop such as a Swiffer that uses disposable pads for your floors.
Determine if your floors are finished, waxed or have no protection at all. In an inconspicuous spot, place a couple drops of water on your floor. If the drops soak in or turn the wood even darker, your floors are natural and have no protection. If the water beads up and stays there for a few minutes, your floors are either finished or waxed. Scrape the floor with your fingernail or a paper clip. If you scrape up some clear material, your floors are waxed. If not, your floors are finished.
Cleaning Finished Floors
The best way to clean your dark, finished hardwood floors with Murphy's Oil Soap. This will lift away the dirt and grime while restoring its beautiful natural look. Use Murphy's Oil Soap's "Squirt and Mop" variety. Squirt some of this product on your floor and take a damp mop with a sponge head (not the dust mop) and mop your floors. You do not need to dilute or rinse the product.
For a homemade cleaning agent, in a bucket mix 1/2 cup of white vinegar per one gallon of warm water. Dip in your mop and squeeze out the excess and mop your wood floors. No rinse is required.
Cleaning Waxed and Natural Floors
Other than dust mopping your floor as mentioned above, the only way to clean your waxed floor is by spot cleaning it with fine steel wool (No. 1 or 0). Then you will need to rewax the spot with a little bit of floor wax, available at your home improvement store. Afterwards, bring back the shine by buffing the area with a clean rag.
If your floors are not treated at all, consider getting your floors finished to make cleaning easier and without the worry of damaging your floor. In the meantime, dust as mentioned above. You can also spot clean. Put a small amount of mineral spirits on a clean rag and gently rub your unfinished dark hardwood floors until they're clean.