Ways to brighten walls without paint or expensive stuff?

Question

My walls are white, I don't like it. My parents won't let me paint. I need some things I could make that won't look cheap that I could do to brighten up my pad.

My room is pretty much pink and purple now.

Answer 1

Posters and pictures. (:

Answer 2

staple fabric then hide the edges using chair rails and square rosettes on the corners