Go Memphis in May
Wear real shoes you don't mind getting caked in mud. Rain boots are best, but if you can't stand them, try a pair of sneakers with laces instead. They'll be disgusting after BSMF or Barbecue Fest, though, so don't take your faves. If you're hoping to hit Beale Street after the park, stash a pair of flip flops or nice heels (assuming you can handle them after a long day at Tom Lee) in your car for after the shows.
Long pants, especially jeans
It's going to rain. Repeat that to yourself: It's going to rain. You don't want to be trapped in the park for hours, hot and drenched, in uncomfortable clothing. Light cotton skirts, board shorts and/or athletic shorts dry out the fastest and don't weigh you down the way denim or heavy khaki would. Plus, it's easier to rinse mud off your ankles.
The color white
Ladies, it's going to rain. Don't be that girl.
If you have them, this is the weekend for contacts. Some shows pack thousands of people skin-on-skin next to the stage. Even if you were willing to reach down and pick up your fabulous prescription frames, you may not be able to. If contacts aren't an option, wear the oldest, most functional pair you can handle.
Unless you're certain those designer threads will hold up against rain, sweat, mud and the SoCo slushy your friend accidentally poured down your back, leave them at home. When in doubt, light workout gear and breezy cottons are best.
Call it what you will, the old adage applies: Just because you can do something doesn't mean you should. Purses and bags are, once searched, welcome inside Tom Lee. But unless you have a genuine need to cart something all-important around with you, a bag will probably get on your nerves. Blankets, though permitted, are almost never needed. You can't take in food, things to play with or decent cameras. Re-evaluate your "needs" before shoving your precious bag into the backs of your fellow concert goers.