Winterize??? Bite your tongue, I'm not ready for that!
Winterizing is really easy, and the link above shows good directions. If you have a manual it may show you where the bypass valves, low point valves, etc are located. It might also give you some instructions specific to your rig.
Me water heater, water tank, bypass valves and winterizing kit (valves off tube fur sucking in rv antifreeze) is located under a dinette seat. The mtg. provided a tiny access door that, if used, would make life difficult. The dealer suggested just leaving the screws off for the dinette seat, which I did and it gives me complete and easy access to everything.
The link above says blow the lines or use the pink stuff. I do both....its cheap and provides extra assurance I'll have no problems.
Good luck!