1. Vacuum the entire floor to remove grit and dirt. A vacuum with a sweeper attachment works better than a broom.
2. Remove dirty, built-up wax with hot water and mild dishwashing detergent and a brush or nylon pad. Or, use a commercial wood floor cleaner. Work in small sections, wiping up any water and wax before moving to the next section.
3. When the floor is dry, apply a quality floor wax. Paste wax is more difficult to apply than liquid, but it lasts much longer. For an even, polished finish, buff the floor with a rented buffing machine.