Fill in minor scratches with a remedy that matches the color of the finish.
Break a walnut in half to color in the scratch of a walnut finish. Rub the scratch with the broken side of the nut so the oil will seep into the scratch.
Use tan shoe polish on light-colored furniture. Make certain the polish stays in the crack and does not get on the unmarred area of the furniture. Use a Q-tip or artist's paintbrush to apply.
A scratch on red mahogany can be colored with iodine on an artist's narrow paintbrush. For brown mahogany, use a tiny amount of dark brown paste wax or a brown crayon.
Buy a wax stick in the color of the finish from a hardware or paint store to repair larger scratches. Ask those in the furniture department to recommend other products they may carry to repair larger furniture scratches or deeper gouges. Follow the manufacturer's directions for each product.