Keep in mind that a belt sander is a powerful tool that can remove a lot of material in a short period of time. To use a belt sander, plug it in or turn it on and allow the sander to get up to full speed. When it's at full speed, slowly lower the sander down to the material with a slight forward motion. You will immediately notice that the belt grabs the material as it sands, so it's important to have a firm grip on the sander to prevent it from being pulled out of your hands. Work the sander with the grain of the wood instead of against the grain, and make sure that you don't leave the sander in one place for too long as it will rapidly sand away the material. It's necessary to frequently check your progress in order to avoid accidentally creating a dent or divot that needs to be repaired later.