This is from page 257 of my 2017 Owners Manual:
I would also put some kind of car cover on it.Vehicle Storage - Four weeks to 12 months
. Discharge the high voltage battery until two or three bars remain on the battery range indicator (Battery symbol) on the instrument cluster.
. Do not plug in the high voltage battery charge cord.
. Remove the black negative (−) cable from the 12-volt battery. Attach a trickle charger to the battery terminals or keep the 12-volt battery cables connected and trickle charge from the underhood remote positive (+) and negative (−) terminals. See Jump Starting - North America for the location of these terminals.