As a veteran tailgater of over 20 years, the biggest tip I can give you is to have a checklist of EVERYTHING you will need to take to the game. This includes extremely obvious things like the food and a cooler, as you will be amazed how easy it is to forget something critical when you are scrambling around at the last minute. I'll also throw in a few pics I've taken over the years of people tailgating around us. Nothing unusual in the pics, just thought I'd throw them in.
Anyway, here is my list that I still use to this day. The only thing it doesn't include is drinks, since that was somebody else's job, I was in charge of everything else. I don't leave the house without making sure everything on the list is packed.
Picnic table (where we eat)
Card table (where you put everything else)
Chairs
Cooler
Food
Grill
Grill brush
BBQ sauce
Chimney
Tongs
Charcoal
Lighter
Newspaper (for chimney)
Oven mitts
Paper Towels
Plates
Plastic knives, forks and spoons
Trash bag
Wipes
Salt and pepper
Plastic Cups
Bottle opener
Wood chips or chunks
Thermometer
Dirty towel (for any major spillage)
Basting brush
Tickets to the game!
Portable TV or radio
Binoculars
Cell phone
Wallet (yes, I even have this on the list)
Some pics: