* You really, really, really don't need the unlimited meal plan. You probably don't need the 200 meal plan, either. The dining hall food is actually pretty good, and I'm generally satisfied with it, but you would get tired of eating there every single meal seven days a week. You probably won't be eating three square meals a day, either-- I always did until I came here. Almost everyone has leftover meal swipes at the end of the year.
*Do rent a mini-fridge, and bring a small vacuum cleaner. The instructions say not to get extra-long sheets, but my regular-sized ones always had trouble fitting on the mattresses (which are extremely comfortable, by the way).
*The metro is awesome, but the costs do add up. Bear that in mind when saving your cash. That said, there are many wonderful free things to do in the city. Sign up for sites like Scoutmob and Groupon that will help you find deals! The metro also frequently has delays, so always leave a little bit earlier than you need to.
*Don't worry about picking a major right away. You don't have to declare until sophomore year. Take classes in areas that interest you to help you narrow it down-- you might like the idea of majoring in International Relations, but you might hate the classes themselves.
*No matter what, you will never get as much sleep as you think you will.
*Don't just cling to the same people that you met during welcome week. The people I know who formed super-super-de-duper close friendships during the first days generally feel awkward around those people now. Take it slow and be open-minded in making new friends-- it's not summer camp, and it's not middle school.
*The Davenport Lounge in the SIS building is awesome, much better than Starbucks. I don't even drink coffee, and it's still one of my favorite spots.
*Wearing WONK t-shirts is not a good idea at all. Students here HATE Wonk.
*Joining a club that you love will change every aspect of your college career. Don't be scared to try new things-- you'll have so much more fun (and if you decide to drop an activity, don't worry. It's the beginning of the year, and people won't judge you).
*Most places on campus are closed after 8 on weekend nights. It's very hard to buy food on-campus in the evenings. Luckily, lots of restaurants off-campus deliver.
*Definitely go to office hours with your professors.
*Smithsonian museums (and the zoo) are FREE! Lots of people don't know that, and they're one of the best parts of the city. You can also get tours of places like the Capitol building for free.
*Best inexpensive and delicious place to eat? Amsterdam Falafel in Adams Morgan. A college student's best friend for sure. Even if you've never had falafel, pay them a visit.