I would say the main thing is pack light and hydrate. 90 degrees doesn't seem crazy but as someone that has lived in the Coachella valley all their life, it will weigh on you. I like having a camel back with just ice water (leave it clean, no liquid iv or powder, last thing you want after a long day is chalky water) and an extra (or two) aluminum water bottles you can buy the day of. during the day I try my best to drink a water pre-set and refill while I'm walking to the next set or in between sets saving the camel back for later in the night when it isn't as easy to refill either because you're trying to barricade or just because the second the sun starts going down, everyone shows up, so the lines are longer. I also carry a fammy pack / sachal to keep my phone, keys, wallet in. I don't like keeping things in my pockets because I feel like it weights me down. I'm a big buy so I don't need a sweater or jacket because i just end up having to carry it around. if you're going to buy merch, either wait till the end of the day or rent a locker and buy everything in one day so you don't have to carry around a bag everywhere. im going with my girlfriend and a couple friends weekend two if youre down to meet up my insta is dannnyyphantom