To properly tie down a motorcycle, you will need two ratchet straps (or tie-downs). Ratchet straps are the best type because they are adjustable and have a locking mechanism. Start by attaching one strap to the front of the motorcycle and threading it through the anchor point on the trailer. Then, attach the other strap to the motorcycle's rear and thread it through the anchor point on the trailer. Next, tighten both straps, so the motorcycle is snug against the trailer. Ensure that both straps are equally tight and that the motorcycle cannot move around on the trailer. Finally, use the locking mechanism on each strap to secure it in place. This will help to prevent loosening during transport. With these steps, you can be confident that your motorcycle will be safely secured for transport.