I would buy an air compressor. at least 6 gallons, and at least 150 PSI peak pressure. also a regulator (pressure regulator) if not so equipped (most 150 PSI compressors are) ..and a blow out plug.
When you finish a tailgate. Find a dump station and empty. If you can lollygag there a while take your compressor and open every valve you got (Faucets, Low points. Water heater drain) and bypass the heater (Open TPR valve too (manual lever) let the water heater drain.. See note below.
Now blow gabriel Blow, Blow the lines till the compressor runs out of air. Then go inside and open the water pump inlet strainer and run the pump for a minute. OH, make coffee before you do all this. Have a cup. while the compressor builds back up pressure.. Then BLOW again, and again and again. After the first blow if you used the ice maker cycle it (Forced cycle) then go out and shut off the water feed after it has drained back.
DO this till you get no more water out (5-10 times) and then go home and park it.