Just disconnect cable form battery. TT have a few things that drain down battery, If they drain to low it kill them & if you leave trailer plug in for long time it over charges them . So if you have a car charger slow charge them for a day or just hook them up for a day or two with trailer plug in to house charging them & then disconnect them. The best way is to get charger that is call a Battery Tender. They sale them At most Auto part store & RV supply dealer.
Also don't forget to blow out your water line or use RV antifreeze. Outside shower to if you have one. IF you done have anyway of blowing your line out or pumping rv antifreeze in, When draining you water heater open your faucet hot & cold side let the water drain out of the faucets & toilet to, to be safe do the above.
2010 wildcat 31ts
05 Ford F350 SD PS