Oak stair treads usually sport a bull, or rounded edges along their length. Choose a spot that highlights the lines richly grained oak, such as honey or a deep color red oak. Satin polyurethane finish will provide a surface suitable for pedestrian traffic and protect the stain.
Education to finishing oak stair treads: sand steps with 100-grit sandpaper. Draw the sanding residue from the tread. Use a tack cloth or rags to clean any dust from the tread. Stir the can of stain gently with a paint stick.
Dip the brush in the bush, and tap the brush on the edge of the can of stain to remove any excess stain by brush. Stroke the wood surface with brush. Paint the steps in the direction of the fibers. Wipe the excess stain with a clean, lint-free. Allow the stain dry.
Apply another coat of stain to the steps. Stir the polyurethane and dip a clean brush into the polyurethane. Slowly stretch the brush between the steps in the direction of the grain. Sand the treads lightly with sandpaper grit 120. Finally, to finishing oak stair treads, apply another layer of polyurethane for the steps.