What makes a long distance relationship work...We fight a lot and I don't know how to make things better...

Quit talking about stupid things. You are arguing about superficial things because you don't want to discuss meaningful things that get to the soul level issues. If you can't discuss the superficial stuff without hurting each other, you will never establish the trusting relationship that leads to true, soul level, unity. Remember, they don't want to attack you, nor do they want to feel attacked by you. Whenever something pushes your button, let him know how you feel, don't blow up, defend yourself, or otherwise.
If you feel defensive, or offended, you need to process something alone and get back to them with it. If I said you sniffed elephant dung, you wouldn't defend yourself because there wouldn't be any truth to it. You might want to slap me for lying, or something, but you wouldn't need to defend your self, because I wouldn't be attacking your self, with truth. When you need to defend the self you have invested so much in, there is something there that needs defending, even if it something you don't want in the first place.
Stop defending your self, write down whatever pushed your buttons, consider it when you are alone and let him know what you find out. If he learns that he doesn't have to attack you to get you to listen, he might start talking about more meaningful things, that both of you will grow through.

It ain't over til its over but face the fact it could end. Last summer I was in a long distance and we started going downhill even though we planned to get married. Just try as hard as possible to compromise and make it work. You have to work through the problem though first! Just keep the communication VERY open.