Here's how I do mine, and how most RV dealers do it also. 3 parts.
Part One- Battery
1) Install Charged Battery in place, connect Black Battery Cable to Positive, White Battery Cable to Ground. Always install the Positive First.
Part Two-Wheels
1) Check Tire inflation and tread.
2) Remove tires and grease bearings, check brake shoes and magnet operation. Torque Axle Nuts and Lug Nuts to specifications.
Part Three-Water (Provided you use the double blow out method)
1) make sure low point drains are open.
2) make sure hot water heater is in bypass.
3) close drain to freshwater tank.
4) Fill Freshwater tank 1/2 full.
5) Close faucet in sinks, tub, shower.
6) Start water pump for 30 seconds watch water come out low point drains. Shut off pump.
7) Close low point drains, start pump, open faucets one at a time, flush toilet, run pump for 2-3minutes.
8) Check water, make sure no pink in it. If pink, repeat step 7 until clear. Refill Freshwater Tank if necessary.
9) Shut off pump, close faucets.
10) Open Fresh Water tank drain, drain tank.
11) Connect hose to city water fill. Do NOT Turn on Yet!
12) Re-tape Annode Rod for Hot Water Heater, install Annode Rod (this is also the drain plug), make sure pressure relief valve on hot water heater is closed.
13) Switch Hot Water Heater Bypass to normal, Turn on Water to City Water Fill.
14) Open Hot Water line at Sink, bleed air out, fill hot water tank.
15) Close Freshwater Drain and refill.
Part Four- Go Camping
note: the Double Blow Out Method for Winterizing is to Blow out the lines and low point drains with 45 pounds of Compressed Air, Flush all lines with Antifreeze, and blow out the antifreeze with compressed air, making springtime water de-winterizing a brief 5 minute operation.