Roll With It.
Paint is one of the easiest, least expensive ways to breathe new life into your decor. Change a room's color and you not only change its look, you change its vibe. Large rooms feel more calming when painted in cool hues, like marine greens and blues. But there are many more applications for paint than just changing wall color. Use paint with stencils to create faux finishes, or paint, well, just about anything: bookcases, tables, lamps, and even floors. Check local retailers for mis-mixed paints, which you can pick up at a fraction of their original cost.

Change of Plans.
If you're like most people, your floor plan is arranged in such a way that all of your furniture is pushed back flush against your walls. Such a layout can look a bit sterile, so try bringing your furniture out from the room's perimeter, and placing pieces on the diagonal - this can lend rooms a sense of movement, taking them from dull to dynamic. Also, experiment with groupings of furniture, creating different "zones" that serve different functions - a reading nook and a TV-watching area, for example. Changing your floor plan might make you break a sweat, but it certainly won't break the bank.

It's the Little Things.
Rugs, pillows, artwork, picture frames, lamps, vases - easy to move around, repositioning accessories are a great way to revamp a room. Rearrange your accessories or rotate them so only some of them are out at any one time. Want to introduce a theme into a room or change one that's already there? Accessories are a great way to do so - limiting your thematic expression to accessories helps to avoid overkill and allows you to easily and inexpensively change your theme when you tire of it.

A Shift in Focus.
Interior designers will tell you every room should have a focal point, a place for the eye to rest. If your room doesn't have a focal point, create one. To make it easier, some rooms have natural focal points: a fireplace, picture window, or wall of built-in shelving. If the room already has a focal point, you can shift it - from the TV to your big, fabulous painting or area rug, for example. Emphasize your focal point by arranging your furniture around it, accenting it with lighting, accessorizing it, or painiting the wall behind it a different color.