Sweep the stairs of dust and debris.
Remove previous stains and debris from the stair surface with medium grade, 80- to 120-grit sandpaper. Move the sandpaper in long, straight lines.
Smooth the surface with fine grade, 160- to 220-grit sandpaper.
Wipe away leftover sandpaper dust with a damp cloth. Allow the stairs to dry thoroughly.
Open the can of wood stain and stir it thoroughly with a stirring stick.
Apply a wood stain to each stair using a paint brush. Allow the stain to dry for 2 hours.
Lightly sand the stained stair with sandpaper. This is only necessary if you are applying a second coat of stain.
Apply a second coat of stain to the stair if necessary. Allow it to dry for 24 hours.
Apply a clear, protective finish to the stairs after the stain has dried. The finish will protect the stairs from wear and stains.