Sand the entire block, including every nook and crevice. Use finer sandpaper to achieve a lighter color. Wipe down the block after sanding with a clean cloth to remove all sand detritus and dust.
Apply a pre-stain wood conditioner or a sanding sealer to the wood with a paint brush.
Apply the wood stain with a paint brush. Stir the oil in the wood stain can before applying to ensure that the color of the stain will be applied evenly. Use a clean cloth to wipe in the direction of the wood grain to remove excess stain. If applying more than one coat, allow the stain to dry for about 10 minutes before applying another coat. More coats will result in a darker stain.
Apply a polyurethane clear finish once the stain has dried, which can take up to six hours.