Paint the walls. Changing the paint color completely modifies the look of your room without having to spend a lot of money on supplies. You can even create new looks by making stripes or painting opposite walls different colors.
Redo the dresser. If you have a dresser in some type of wood, make it look new by sanding it down with a fine-grit sandpaper and applying stain. You can also paint the dresser to match your room's color scheme and purchase new handles from the hardware store to update the look without spending a fortune in the process.
Add a small area rug to the center of your room. Area rugs are available in a variety of colors, thickness and styles and can change the look of your bedroom without you having to spend a fortune on new flooring. You can take it out of the room easily to clean and move it around if you reorganize your bedroom.
Modify your lighting. Lamps are not too pricey and can completely change the look of your room. You can even replace the shade on an existing lamp. Some light fixtures have shades designed to transform your white light to a shade of blue, red or purple. Search at flea markets or consignment shops for cheap lamps and shades.
Add or change the curtains. If you're crafty, visit a fabric store to purchase fabric, and make your own panels. You can make them the same color and pattern as your walls and bedding or make them contrast significantly for a bold statement.