Don't forget to drain your WH tank. A word of caution, open the relief valve on the tank first to let off pressure and then remove the anode plug (if you have a suburban WH) (1 1/6" socket) and drain the tank. Make sure the water is not hot also. If you happen to fail to relieve the pressure on the tank it will be a certainty you will remember the next time. Also is a good time to take a look at any erosion of the anode rod to see if it needs replacing.
Lots of "You Tube" videos on the subject of winterizing and it is quite generic to the procedure for almost all RV's.
2014 Palomino Puma 25RS
2011 F-150 Super Crew XLT
Days camped in 2014 - 23 Camped 2015-47
Camped 2016-71, 2017-33, 2018-29 booked