Raymond, Our Coolhorse Trailer Shop Foreman, goes over steps to winterize your trailer using RV Antifreeze. 

First you need to drain your fresh tank.  Then locate the Hot, Cold, and Bypass valves on water heater.  Use the bypass valve to make sure none of the antifreeze gets into the hot water heater.  Next remove the Anode Rod from the water heater.  The Part Two video shows Raymond removing the anode rod if you need help with this step.  Use the bypass valve to pump the antifreeze into pipes.  Run water through both Hot and Cold sides of each sink, appliance, toilet, shower, every water source that you have, and run the water until antifreeze comes out.

Part Two covers how to remove the anode rod and blow the water out of your trailer.  This does not clear water our of the pump or water heater, so this method is not recommended for those in extremely cold climates.