Paint the walls a light color. Use variations of white, cream or pale blue to maximize the wall height. Paint the window and wall trim a lighter color than the walls to make the walls appear farther away, giving the illusion of a larger room.
Arrange the furniture using the window as the focal point. Upholster or paint the largest furniture item a similar color to the walls. Use small scale furniture that has more than one function. Center an upholstered storage ottoman in the room to serve as a coffee table, additional seating and storage. Maximize the space under the bed with boxes or drawers in a small bedroom. Place side cabinets with drawers or shelving adjacent to seating areas in living areas. Use furniture that is light or has a reflective surface.
Position a floor mirror on the wall opposite the window. Create the illusion of two windows by framing the window and the mirror with sheer drapery panels. Hang the drapery from floor to ceiling to accentuate the height of the room.
Install track lighting on the ceiling or on the wall. Aim the fixtures to highlight different areas of the room. Hang wall lamps over tables to free up surface space. Position floor lamps to make the room appear and feel larger. Flank the window with lighting to reflect off the mirror at night.
Limit decorative accessories. Hang a single, large piece of art on one wall. Keep floors free for added spaciousness. Create the illusion of more floor space by removing area rugs.