Here's some info that might help! If you don't want to drive to a spot to tailgate, then I suggest planning ahead to bring some food or beer (or even some money to pitch in) to join someone else's tailgate.
Here's some info I found on spots to tailgate. I'm not sure how early all the lots open, but 10AM sounds about right to me for when people start showing up. Hope you have fun and enjoy the game!!