Make sure your floor hasn’t been waxed before painting, and remove the wax if it has. Follow these tips when painting a floor:
Rough Surface: Using a square pad sander (or by hand), rough up the finish on the floor with 150-grit sandpaper. You don’t need to completely sand them, just remove the gloss from the old finish.
Clean Floor: Thoroughly vacuum and damp-mop the floors, to remove all the dust. Allow them to dry completely. Applying paint to floor with paintbrush
Apply First Coat: Using a brush or roller, apply the first thin coat of floor paint. A brush will give a smoother finish, but a roller is faster. Resist the urge to glop on the paint – it won’t dry! Start by cutting in the edges with a brush, then use a brush or roller to work your way towards the door so you aren’t painted into a corner. Allow the paint to dry for 24-48 hours, until it’s dry enough to walk on.
Smooth Paint: Lightly go over the floor with 220-grit sandpaper, to smooth out the grain and give a sleek surface, then clean the floor to remove all the dust.
Apply Second Coat: Apply a second thin coat in the same manner. Paint your way towards the door, then get yourself out of those fumes! Some paints may require up to three coats.
Decorative Touch: After your base coat is good and dry, you can add stripes, motifs, or other designs. Use safe release painter’s tape so it won’t pull up the base coats.
Seal Floor (Optional): For high-traffic areas, you may want to coat the finished floors with a clear polyurethane.
Let Paint Cure: Within a few days, you should be able to walk gently on the floors, but it will be several weeks before the paint is fully cured and the smell goes away.
VIDEO: How Repaint Wood Floors
Article Source: http://www.todayshomeowner.com/painting-wood-floors/