Dorms and apartments often have basic, overhead lights with little built-in ambient lighting. Purchase floor lamps for extra lighting in a shared space. Table lamps can also be used just as effectively. If you have exposed pipes in your dorm room, for example, decorate those pipes with white Christmas lights. If your apartment is the party hot-spot, use black lights, neon bar lights, or lava lamps for additional effect.
Design your walls with posters, knickknacks, or any other desired décor. Depending on your dorm's rules, for example, you may not be able to nail or screw anything into a wall. Use "earthquake putty" if your dorm walls are cement or use "T-pins" if you are not allowed to use nails. If you're a guitar player and live in an apartment where using nails isn't an issue, for example, hang your guitars up on the wall with U-shaped tool hooks. Place posters directly against the wall with earthquake putty or T-pins, or place posters in a sturdy frame to accent the poster and wall color.
Measure your dorm or apartment space before bringing in large furniture items. In addition to dorm beds, futons function great as extra seating and sleeping space. Apartment living rooms offer more seating option choices, such as room for sectional couches, arm chairs, 3-person sofas, and love seats. Come to an agreement with your roommates as to which furniture pieces can be used in the living room or other shared space. If you plan to host frequent guests, avoid placing nice decorative pillows on seating arrangements.
A purposefully messy appearance can be decorative and functional. Stack loose books and magazines at the side of your seating arrangement. Lean posters (if in frames) against the wall as if they will be hung up soon. Place CD and DVD cases in a disorderly, but decorative fashion on top of your TV or DVD player. Leave clean kitchen utensils out on the counter and pots and pans on top of the stove. Only place things on the floor that belong on the floor, such as bean bag chairs, floor lamps, bookcases, etc. Focus the mess away from the floor so you and your guests have room to freely walk around your dorm room or apartment.