First and most importantly, show up way before the doors open, especially for a rally on a weekend. Don't worry about being bored, you'll make plenty of frens in line. However if you show up when the doors open you'll be too far back. I would try to show up at 6am. There will still be plenty of people in front on you but you'll get good seats (and you'll remember see GEOTUS up close for the rest of your lives!).

Second, I never bring a chair but you can get cheap chairs from DICKS according to other rally goers (though, also, I don't want to be supporting DICKS). You can also rent one for 10 bucks from the vendors. Either way expect never to see that chair again. You can bring it back to the car if you want however, though to be honest I've never seen anyone do that.

There will be vendors selling food and drinks and there will be bathrooms, you can get out of line to use them and your frens will save your seats. To make a fren just turn to anyone there and say "Hi, I'm [you're name]" and BOOM! instant fren for life.

Also, if there's paid and unpaid parking park in the unpaid lot. Hasn't always been an issue when I've went but getting out of there is hard and I've gotten stuck in the paid lot for over an hour because they weren't prepared and only had one exit for everyone.

Other than that, have a great time!