What to bring

General tips

Pack for all weathers. It may be June but it can still get pretty cold, especially at night or if it's wet. Similarly just because it's overcast doesn't mean you can't get sun burn and heat stroke. Either way make sure you have the things you'll need to be comfortable whatever the weather
Plan to walk. The site isn't huge but it's still a 10 min walk from one end to the other and there's lots to see all over it so make sure you have shoes you're comfortable walking in for a while (we recommend boots). If you don't walk a lot, some blister plasters are also a good idea.
Stay hydrated and fed Walking around all day outside will take it out of you, plan to eat and drink water, probably more than you normally do.
Aim to sleep well (bring earplugs and comfy things) Three thousand odd people make a fair bit of noise, whether it's kids in the morning or bigger kids at night. Whilst we have quiet and noisy ends of the site, sound travels and so do ducks, so to help get a good night's sleep, some earplugs you can sleep in are a great idea.
Know your limits and be kind to yourself. EMF is a lot, there're thousands of cool people, pretty lights, awesome sounds, new things to learn, food and drink to try. It's great, but it can be a lot, it's ok to take time for yourself so scope out quiet places you can sit to recharge (a walk up to the obelisk is a great way to unwind). Just as much make sure you stay hydrated and if you need to: nap!

An example packing list

Tent
Sleeping bag, bed roll/air mattress, electric blanket
Changes of clothes (make sure you have at least one full change because if you get soaked it can take a while to dry out)
Wash stuff (including shower stuff & towel)
Flipflops/other easy removed footwear (for going to the shower)
Torch (a head torch is generally favourite)
Water bottle
phone charger & battery
Earplugs
Long (>40m) 13A extension cable (ideally with Ceeform (2+E) connector) if you want power to your tent (for phone charging, electric blanket etc)
Money we accept cards and offer cashback from the bar.
Things to craft/hack/play with
A day bag, a small rucksack to carry water/laptops/cameras around the site in

Valuables

Many people do bring valuables to the site (e.g. laptops, robots, 3d printers, lathes) but please be aware that there is no attendee-available secure storage so you should consider carefully what you bring and how you'll look after it. That being said the event is very friendly and leaving items in tents is generally fine.