1) Paint is the most cost effective way to dramatically change a room. If you fear picking the wrong color or the wrong set of colors, most paint stores have brochures with varied paint combinations that you can select from with confidence.  Purchase the smallest amount available in that color and paint it on a piece of cardstock (or several pieces) that can be moved around the room to see how the color looks in different light.  Leave the paint on the walls for at least a week before making a decision.

2) Hang your widow treatments high.  Hanging your drapes, curtains, etc. at least 1 foot higher than the top of the window or the window molding adds visual height to a room and makes a significant statement.  If you don't have 1 foot or more, hang the window treatments just below the ceiling.  Hanging exterior mount roman shades/blinds higher than the top of the window allows more light to enter the room when the widow treatments are raised to its highest level.

3) Choose pieces that serve a dual purpose (especially in small spaces). For instance, choose an office desk that can also serve as a dining room table or an extra table for a party.  Select ottomans that have storage and can serve as additional seating or an additional coffee or side table when needed.

4) The most common design mistake homeowners make is to hang their pictures/art too high.  In general, the center of the picture should be 59 inches from the floor (known as eye level).  If you are very tall you can adjust this rule slightly, but pictures should not be centered between the furniture and the ceiling.  To add additional flair, try "framing" your furniture (sofas, lamps, articles on side tables) with the art rather than hanging it symmetrically on the walls.

5) Don't overlook discount stores for fantastic and inexpensive accessories.  Places like Marshalls, TJ MAXX, HomeGoods, Target and World Market have great accessories that are knock-offs of much more expensive pieces.  Get the best selection of goods by visiting these places on Wednesdays and Thursdays (when the inventory has been restocked) and beat the weekend crowds.