I get asked often "what's the best way to store my board for the winter?".  The best way to store your board for the season is in a cool, dry place out of the elements. It can be inflated or deflated. Rolled up in the bag, or on a shelf. Whatever works best for you. High heat and prolonged exposure to intense, direct sunlight is really hard on the materials and can degrade the glues and foams used in the boards construction, so car trunks or hot sheds/ storage units are not ideal. At the end of every session, I wipe down my board, deflate it, and put it in it's bag and store it in a gear closet. That's worked for us, and will probably work for you too.