Set up apartment rules before moving in, both sign it, print it, and stick a copy of it on the fridge. This includes chores and having people over, expenses such as electricity and water, cleaning and use of common ground (kitchen, my dishes vs your dishes, groceries, toilet paper, toothpaste, trash bags, use and cleaning of microwave/fridge/kettle/toaster if you separately own these and share) and general rules such as no smoking inside the flat (trust me, you don't want that, you never get it out and it decreases property value of curtains, carpets, furniture, and the actual walls and ceiling retain yellow goop).

Friends can feel entitled to screw you over because you're friends, so srt up this shit beforehand and stay friends after. Too many people begin as friends and end up hating each other's guts after.

We've been friends since early middle school, and we're pretty tight. He moved away the summer after 8th grade, but we kept in touch.

He's a good dude, and I can honestly say I trust him. He's had probably, 100 opportunities to screw me over before. Not gonna lie, he's kinda emotionally distant, and maybe a little full of himself, but, he's still my best friend.

Even if you're really close, having apartment rules/cleaning schedule/etc. is crucial. And always talk it out if something bothers you. It's better to have a couple awkward conversations than lose a friend for good.
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On a practical note, pack a "day-of" box that has anything you might need immediately - clean sheets, hairbrush, phone charger, etc.
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Look up tenant laws for your new state so you don't end up getting screwed by shady landlords.
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Finally, make time to chat/skype with the friends/family you're moving away from. It can suck to be relatively alone in a new place.

Just to confirm what has been said:
Put up clear rules, especially for cleaning, laundry and dishes. Every person has another idea of tidyness and in my experience in room sharing the best way is to have a switch-pattern to clean the rooms you are using mutually (kitchen, living room, bathroom). This way every week you're taking turns for e.g. the kitchen and you will most likely clean the spots and corners your mate doesn't and vice versa. If you have no dish washer, buy one, better sooner than later. Dishes are proven to be a relationship killer!
Don't buy your food on one bill, buy each to their own and mark what's yours. The closest friendships are breaking over money and in the most cases it's not over one owing a grand to the other, but over the 1.29$ peanut butter.
Never forget: Even your closest friend didn't experience having you around all the time and living together is always a challenge that needs loads of willingness to compromise from either side.

Divide rhe chores, divide the god damn chores. I am suffering it so I know.

Unless you really have a HUGE amount of furniture, you're probably better off selling your big stuff and just buying new when you get there. I sold my $100 bed and saved $300 on a truck

We do actually have a rule in place for food. The shared account is for like, groceries we both use, of course, but, for stuff like hot pockets, or instant foods, if you didn't buy it, don't touch it. As for dishes, if you dirty them making your own food, you can clean them yourself. If one person cooks food for both, the person who didn't cook cleans the dishes. My friend is also a bit of a neat freak, so really, I think the biggest problem would be keeping things clean enough. Between me and him, think Left and Right Brain. Like the Bo Burnham song thing.

Keeping things clean is the issue in all shared apartments. Put up a cleaning schedule for each of you and make clear there are almost no exceptions or excuses for not doing the part assigned to you.
It sounds horrible but believe me, it's the only way to split the work equally

My soon-to-be-roomate has already told me that he'll fite me if I mess up his cleanliness. (We've been friends since like kindergarten, this is normal)