How to lose weight without counting calories?

Hi Nancy, former RA and summer RD here, who happens to be a professor now too (aka dining halls cannot be escaped), with some tips I've received and figured out over the years.

1. Visit your school's nutritionist/dietitian. Every college or university in the US has one, because they need them to receive federal and state funding for food services. They can help you navigate your particular institute's menu options.
2. Don't use a tray when in the dining halls. Several studies have shown that students eat more and waste more food when using trays. Many school's have done away with them for this reason. They do, however, make excellent sled and boot trays in the winter.
3. Most school's already use smaller-than-home dinner plates, but if yours doesn't, use the cereal bowl for the same mind trick.
4. Depending on your school's food service contract, they may already be logged. I work for a SUNY school that uses Sodexco, and whenever I purchase ala carte it's generally already available. Sometimes I have to adjust for additions, such as the olives I like on my subs. But the general thing is there. When it's not, I usually find a restaurant equivalent.
5. You don't eat dessert after every supper at home, so, even though it's available, remember, you don't need dessert with every meal. Dessert is a treat. Keep it for once or twice a week and then you're neither denying yourself, or overdoing it.
6. Beware the room snacks. Keep that fridge stocked with low-call, nutritious food. Apples are a good one because they keep for-eve-er, but yogurts, oatmeal/cream of wheat packets, and single serving cheese like mozz sticks are also good to keep around. Watch out for the things like Pop Tarts and cereal/granola bars and anything that comes in a can or microwaveable cup. One every once in a while is no biggie, but those bad boys pack a punch if you're eating them constantly. I also recommend those little 100 calorie packs of things, if you have the willpower to not eat 10 of them in one sitting. I keep them in my office desk for when I have paper conferences or a student says they forgot to eat.
7. Keep a water bottle on you. Always have one in your bag and one in the fridge. Reusable so you don't kill the planet too. If you have a drink in your bag, you'll be less tempted by the vending machines. I keep the water bottle and a thing of Mio drops for those days when the water just isn't enough to this day. The vending machine is evilly placed outside of the classroom I generally teach 3 back-to-backs in.
8. Beware the coffee drinks. When everyone is running to the cafe between classes to get mochas, choose a coffee coffee, or a skim-milk/sugar free vanilla latte type thing, and always get the small. It's almost unavoidable it's so much college culture now, but you're not drinking coffee drinks because you're thirsty or hungry, so go for small. Want more caffeine, ask for an extra shot.
9. Beware of the "Night Owl" cafe, or Late Night. Nothing good comes of it. The food is always bad for you. But if you must, look for the simpler options and share with friends. The less junk on them, the less likely you are to regret it later.
10. Be kind to yourself. When you slip, remember you can start again tomorrow. You're going to slip, and it's ok. 3500 calories to make a lb. Write that someplace you can see it, so on a day when you slip, you can remind yourself it was just an oz. or two no matter what the scale says in the morning (All of that salt and sugar leads to water retention). Food is such a big part of campus life. Free cupcakes, free pizza, free candy, but rarely free bananas. Don't always abstain, or you'll feel resentful, but one or two a week is enough!
11. When in doubt and absolutely tied, use the handful method. http://www.bodybuilding.com/fun/the-handful-diet.html

Good luck! You can do it!