i have never iced a deer, i iced my first turkey. Froze a gallon of water, then cut the plastic off and put it in the cavity. This was because i shot it, and then my dad kept hunting for a while, so by the time we got back to the truck it could sue the ice.
last year we hung tarps in the corner of the garage and put an air conditioner in the window, making a makeshift cooler. it kept the deer cool enough until we could quarter them. Lost all that meat when our freezer out there broke though