Things You'll Need
Can of polyurethane
4-inch stain brush
Polyurethane is a type of wood stain that can be applied to natural wood to help it retain its appearance and durability. If you have a polyurethane wood floor where parts of the finish are starting to wear off, you can re-stain these areas without sanding the surface. However, if you plan to re-stain the entire floor, then sanding the surface to remove the old finish is recommended.
Open the can of polyurethane, and use a paint stirrer to thoroughly mix the contents. Be sure to drag the polyurethane on the bottom of the can up to the top.
Pour a small amount of the polyurethane into a plastic dishpan.
Dip a f4-inch stain brush into the dishpan and wipe the excess on the edge.
Brush the polyurethane onto the wood floor surface moving in the direction of the grain.
Wait for the polyurethane to dry and check the color. If it needs to be a bit darker to match the surrounding wood, apply one more coat.