I can get you started. I have a B plus, others can fill in the blanks.
Drain your tanks. Fresh, gray and black.
Find and open your low point drains. Open your sink faucets to allow air in.
Remove your water heater anode rod or water heater low drain. Drain your water heater.
Find your water heater bypass valves (should be 2) put them in bypass.
I use low pressure air to force water out of the system at each faucet including the shower.
Close the low point drains, close the tank valve between the tank and pump tee. Open the valve to the pump inlet. This should have a hose attached. Stick the hose into an antifreeze bottle. (Propylene glycol). Turn on the pump and open facet valve to fill lines with antifreeze.
Add antifreeze to the drain traps, sinks, shower.
Most people turn their camper battery power off at the disconnect. Better if you charge the battery to over 80% first.
Also we like to clean the refrigerator and add baking soda to absorb odors.
