There are a lot of ways to jazz up a room without
painting.
A great theme for room that you can't paint and don't want too girly is
zebra/animal print. Because your have white walls, you can go as wild as
you like.
Add a new comforter to your bed. Choose a hot, bright color like
turquoise, red, or hot pink. With some new throw pillows a cuddly
blanket or two, your bed will look like an ad in a magazine.
On your floor, add a large zebra area rug. Something like this
Zebra area rug would be
great in a room with white walls and bright color everywhere else.
Posters are relatively inexpensive and are a great way to liven up the
walls. You can buy posters online or at your local Walmart. As well, buy
a bulletin board and some picture frames. You can also add some word
art to your walls, and there are lots of sayings you can choose from.
Don't forget about curtains. They make your room cozy and add color as
well.