ITEMS YOU MUST CARRY.
BOTTLED WATER. If festivals let you bring your own drinking water, do it, as water tends to be overpriced inside the gates. If the festival doesn't allow outside beverages, you can usually bring your own reusable water bottle and fill up at a tap somewhere inside.
LIPBALM/CHAPSTICK. (YES for dudes too.) Any sort of chapstick will do. Better yet, Vaseline. You will be surprised how sad you can be with dry lips.
SUNGLASSES. For obvious reasons. The laser show at night!
PANTS & HOODIE. Keep it simple. Its hot during the day, but cold at night....
FLIP-FLOPS & SNEAKERS/BOOTS. Sneakers/boots for the partying and extreme dancing. Flip-flops for the improptu showers in the middle of nowhere.
MINT STRIPS. Cuz lets face it, you will lose your toothbrush. And no-one ever wants to have that "Eish, your breath seriously stanks." conversation.
FLASHLIGHT/HEADLAMP. Serious dork factor, but they will be really convenient (flashlight strap around your head on an elastic band) when searching for stuff at night, for nighttime Port-O-Loo trips (the scariest thing ever), for seeing your cup and mixer when mixing drinks, for setting up your sleeping space and all sorts of other things.
TOILET PAPER AND/OR BABY WIPES. No one ever wants to admit to this, but every seasoned festivarian knows to bring a couple of rolls of Velvex from home. Port-O-Loos run out of toilet paper pretty quickly and the replacement rolls are usually the super-thin, super-scratchy, wipe-fifteen-times variety. You might need this to take a "hoe-bath"/“passport”/"hippie-bath" too. Or after a trip to the porta-potty. Suck up the shame and carry them. You'll be glad you did,was glad to have with me.
TINY FIRST AID BAG. Throw in some pain-killers, some Imodium, a couple Elastoplasts and a disinfectant. That's all you need. Searching for emergency care at festival grounds is usually more of a hassle than just stuffing these four things somewhere in your bag.
CAMERA. You can't go to a music festival without your camera! Some festivals have rules about what types of camera you can bring (no movie cameras, etc.), but every outdoor festival lets you take snapshots. Make sure at least one of your friends has a camera on hand. Sidenote: it's generally in poor taste to snap flash photos while a act is on stage, so turn your flash off at night.
PORTABLE COOLER. Some festivals don't allow coolers, some do. There's nothing quite like a chill beer on a nice festival afternoon. If you're staying for more than one day, they can easily hold left over food too(pizza, chicken) and the long coolers can also double up as a bench.
MASAI SHUKA/KIKOY. Perfect for sitting on, wearing, blankets, ponchos, shade. The versatile African shuka/kikoy is a staple at every festival.
BACKPACK. Between a cooler and your backpack, you will be carrying just about everything you need for the entire festival. [Ladies, don't pack your things in a purse/sling handbag. It just isn't practical at a festival; it's tough on your back and they generally don't hold as much as you need. Carry a purse as an accesory, not as your bag.]
ITEMS YOU SHOULD LEAVE AT HOME
1. Indian feather chief/Pocahontas headdress (I have seen too many disasters in this)
2. Flannel shirt (NO)
3. Gladiator sandals
4. Body/face paint (sweating + body paint = smelly hipster creature)
5. Kanye-West-esque glow in the dark sunglasses. ( are they even sunglasses? What are those things? Seriously.....)
5. Babies (seriously, I've seen babies there. HUH???)
6. Frugalness – just come to terms with it, you’re going to spend way much more money than your strict budget.
7. Your Sony DSLR &?*@^#!!%*?@&;£^)#&£%^&^* camera – I'm sure there is a good reason you had to name all the letters and numbers in your one-of-a-kind camera (like I care). So yes, leave it at home. Your paranoia is completely warranted. Your camera will definitely explode.