1. Host a backyard crawfish boil every year for about ten years
    It'll start small with about 20 close friends the first year and eventually grow via word of mouth to be about 300 people that you mostly don't know.
  2. Purge and boil about 150lbs of live crawfish
    You'll need a kiddie pool to keep them alive for the duration of the party, use plenty of cayenne and Old Bay and boil them with a variety of hand held veggies like corn and potatoes and dump the batches on a big table covered in newspaper, Louisiana style
  3. Make sure everything is so spicy that the kids stay hungry and the adults are compelled to slam beer after beer.
    Suggested by @karen
  4. Start early and go late
    The first batch should hit the tables around 3 in the afternoon and the last batch around dusk. The crowd will be drinking continuously during this time and the families will begin thinning out at things get rowdy around 8pm.
  5. Recruit a bunch of bands to play
    Get a range so that you have pleasant bluegrass picking in the early afternoon, something weird like ska around transition time and then punk or maybe surf rock for after dark. The bands don't have to be good, just free.
  6. Call the cops when one guy throws a full beer can at another guy who ducks, causing an unaware band member's girlfriend to be hit in the face during her boyfriend's set which is now over because he lept from the stage to pummel the beer thrower.
    Did everyone get enough to eat? Thanks for coming.
  7. Have those bands invite a bunch of their "friends" to come see "their show"
    Who are these drunk assholes ruining my party?
  8. Call it quits on this annual party, because you're too aware of liability law to deal with this shit anymore.
    It was a great run though, wouldn't change a thing.