After the final sanding, I vacuumed and taped the walls, then was ready to apply my topcoat. I chose Bona Mega to match the existing finish and applied the Mega using a 5″ lambswool applicator, following the manufacturer’s directions. It was a surprisingly forgiving process–pour the finish and spread to an even coat with the applicator. So long as the next coat is applied within 48 hours, you don’t need to sand between coats, but I did hand sand with 220 grit before my final coat. Because stairs are high-traffic, I applied four coats over the course of a weekend. While it cured to final hardness, we could consider runner options.