How can I effectively repair scratches on my furniture using polyurethane?

To effectively repair scratches on furniture using polyurethane, follow these steps:

1. Clean the scratched area with a mild detergent and water.
2. Sand the scratched area lightly to smooth out the surface.
3. Apply a thin layer of polyurethane using a brush or cloth, following the wood grain.
4. Let it dry completely before applying additional coats if needed.
5. Sand lightly between coats for a smooth finish.
6. Repeat the process until the scratch is no longer visible.