Wrap the loose nylon strap around your cargo. If you're securing your cargo to the walls of a trailer, be sure to feed the strap through the eyelets along the walls. When the strap is more or less in place, bring the loose end and the ratchet together in an easy-to-reach place.
Thread the strap onto the spool. The spool is the thick, smooth bar on the opposite end of the ratchet as the handle. The strap must be fed into the spool from underneath, pulled over the bar and pulled out the other side.
Pull the loose end of the strap as tight as possible to feed the majority of the slack through the spool.
Ratchet the strap tight. Grab the handle on the ratchet and lift it up so that it is perpendicular to the cargo it is holding. As you pull it back down, the strap will tighten. Repeat this process as necessary until the cargo is sufficiently secure.
Relieve the pressure on the ratchet when you want to remove the strap. Lift up the ratchet handle and look underneath for a release switch. This switch may look different on different ratchets, but it is usually the only obvious moving part located underneath the ratchet handle. Once the ratchet has been released, you can pull the loose end of the strap through the spool and remove the strap from your cargo.