1. You play it safe.
"Instead, put a large-scale printed fabric or wallpaper on the walls and even the ceiling. It's easier, safer, and less expensive to be dramatic in a small space. You might get tired of a bold print in the main living area, but it can make a smaller, less-used room an exciting space to spend time." — Victoria Neale
2. You cram the space with too much stuff.
"A large piece of furniture can actually make the space feel larger, as long as it's selected carefully. For instance, if you have the benefit of high ceilings, a tall cabinet appropriately placed has the effect of drawing one's eye upward and away from the small footprint of the room. Just make sure every piece counts and holds its place and lets your eye rest." — Laura Kirar
3. You dive into decorating without a clear plan.
"Decide everything that needs to happen in a room, and then work that legerdemain, baby. Divide a room geometrically into task-oriented zones — working, sleeping, relaxing, dining. Think in halves, quarters, or even on the diagonal and assign a function to each section." — Elaine Griffin
4. You don't pay enough attention to wall and floor color.
"Lighter walls and lighter floors do automatically give the illusion of more space." — Mary McGee
5. You rely on small furniture.
"Dark colors and just a few pieces of large-scale furniture, with the appropriate lighting and accessories, can give a room a larger, more luxurious feel." — Mona Hajj
6. You miss the silver lining.
"Turn it into a jewel box. For instance, I turned a small room in my apartment into a luxurious retreat. I upholstered the walls in a soft chalk-striped brown wool flannel, coffered the ceiling applying custom-designed 'faux bois' wall covering in the coffers, laid a h red carpet, installed a flat-screen TV on a flexible mount, hung an oversize faux-tortoise-frame mirror to create more dimension, and, finally, designed a custom-made sectional sofa to optimize the space. Now it's a cozy space my whole family uses." — Philip Gorrivan
7. You assume your walls should be white.
"Paint the room a dark charcoal gray or Ralph Lauren's Black Truffles, one of my favorites. This will actually really open up the space." — Paul Mathieu
8. You don't consider going with custom pieces.
"Custom upholstery is essential if you want to avoid burdening a room with furniture that looks like it's on steroids. You should have furniture made in the correct width, height, and depth for the scale of a room. For smaller rooms, I try to avoid anything over 36 inches deep. Better not to overpower a room with the steroid-injected, super-deep models made to fill titanic spaces in McMansions. Bigger is not always better." — Todd Klein