Have ready a steam pot that has a basket insert, pour the beer and seafood seasoning into the pot, cover and bring to a boil. Place the crabs into the basket insert and drop into the boiling liquid and steam for 20-25 minutes or until the crab shells turn red.
Cover the table with brown paper and set out crab cracking tools and anything else you have in mind to go with the crabs other than ice cold beer, steamed shrimp, grilled or steamed corn, lemon wedges and lots of dampened bar towels (big bag at Sam's or Costco). Everyone likes something a little different to dunk some of the crab in, but just enjoy the crab.
When crabs are done you can serve them on a huge platter or on a covered picnic table just pour the crabs on the paper. Sprinkle with more seafood seasoning. Now this is festival food, but that is the closest that I'll ever get to a fair