Bring the minimal amount of things you need. When packing for your dorm, think about everything you'll need first--a small desk and a twin bed, possibly a microwave or mini fridge. While you are tempted to bring that cute chair or some other decorative décor, once you get it there you may regret it, so stick with the basics.
A bunk bed frees up a lot of space in a dorm room, so you may want to either build one or purchase one. Instead of a bed underneath your top bunk, save the area for free space where you can put a desk for working. You can also place a mini fridge or some other necessity, possibly a small chair.
If you can't provide a bunk bed, you can elevate your bed on blocks or 2x4s and purchase storage bins. Measure the space under your bed, and head to your local hardware store to find bins accordingly. You can keep things like winter clothes in them during warm months or any knickknacks you can't find a spot for.
If you have extra cash or perhaps as a graduation gift, ask for a small flat screen TV, which can free up space in a dorm room. You can even find some available with built-in DVD players, which free up more space. Mount it on a wall that is convenient for you to view.
For those small dorm room closets, purchase a closet organizer. A cloth shoe rack that you can hang on your door is perfect if you just can't part with your favorite kicks. Measure your closet, and head to your local décor store to find one that fits accordingly. Using door space with things like shoe racks and hooks is an effective way to make the most of space.
If you have a small mini fridge in your dorm, don't let it get overcrowded with food or food that is past its prime. One option is to designate a weekly grocery trip and plan out food to eat for that week, and purchase only what you'll need and know you will eat that week. Also if you have a roommate, designate a section of the fridge that is yours and a section for them, and label foods that belong to you with your name.
Stick to wall décor. While you may have a cute centerpiece or sculpture you love, it'll only take up floor space. Instead stick to posters and window treatments that won't invade space. For some exciting lighting, hang Christmas lights around the room to give it some sparkle without sacrificing space.
Purchase a small plastic basket to store everyday bathroom needs, like your toothbrush, toothpaste, face wash and anything you use in the bathroom daily. Keep your basket in your closet or by your bed so that when you head to the communal dorm bathrooms in the morning, it is easily accessible. The plastic basket is light to carry and keeps your toiletries all in one place instead of all over your dorm room.
If you are going to college near your home and plan to visit home at least every couple months or so for breaks, utilize the space you still have there. Instead of packing all of the clothing you'll need year round, only pack clothing that is appropriate for the weather over the next couple of months until your next trip home, which can free up closet space for your dorm room.