Welcome, I know you will have a great time. If you don't have accommodations yet, I recommend you start on that right now. Find a place to stay. Hotels book up way in advance -- most are overpriced like the French Quarter in Mardi Gras and have two night minimums. If you don't have a place to stay in Tuscaloosa, Birmingham is only about 45 minutes away and you can usually find a place to stay there a lot cheaper, if you don't mind driving. Just plan to spend some time on the Quad hanging out after the game because the traffic is difficult.
Parking depends a lot on where you are. I have two favorite options. One is to stay on the end of campus near McFarland Blvd. There are several lots generally referred to as the soccer lots. You can pay and get a pass you print out on line. Shuttle buses take you from there to the Quad and drop you off about two blocks from the stadium (near Morgan Hall if you are familiar with campus). It is a hike, but you can walk to or from if you don't want to wait for the buses. They run really steadily before the game and after they line up at the corner of the Quad where they dropped you off. From there you can route north through several designated routes to get back on the interstate towards Birmingham. Avoid McFarland Blvd like it is covered in Ebola virus. The other option I have used is to park at the designated parking garages in downtown Tuscaloosa. That's the other side of campus and a bit further away. However, I've found getting on the interstate easier from that spot. I do NOT recommend that you come to campus without a place to stay and a place to park. It'll just make your trip so much easier.
As for tailgating people set up all over the place. The Quad is the heart of it, but there will be tailgates everywhere. I recommend you check in here closer to time -- Tidefans are usually quite friendly about inviting you to stop by and say "hello". Some posters have been in the same places for years.
Again, if you've not been on campus before it is a truly beautiful place. If you can manage, it is good to get there a day or two early on a big trip like yours and see things before the crowds build in. The permanent team captains hand prints (and later footprints) are in the concrete around Denny Chimes. Sadly, some of the older ones have started to deteriorate, but this is a cool thing to see. Still have the photo of my kids putting their hand prints in Joe Namath's and Ken Stabler's when they were in elementary school.
The tips in the other thread are all good. Again, I recommend you check back closer to time -- often there is a new hot spot to go for dinner or drinks and one from the past may have faded away.
Good luck planning your trip and RTR.