Fresh oil change
What kind of surface is the car going to be over? If its concrete, put some floor dry under the car to help from condensation rising and sticking to the underside of the car.
Make sure you have good coolant in the car and be sure to test it to see how it stands.
Put the car on stable jack stand to help your tires from going flat.
Fill tank with gas and add stabil. Ive never had trouble with having gas in a tank for a year plus.
Disconnect battery.
Put ivory soap (bars) in the car (and glovebox), in the trunk and under the hood. This will prevent mices from making it there home. Also downy dryer sheets will work.
Put steel wool in the tailpipe, again with the mice.
Thats all I got for now