Good posture

Stand (and Sit) Tall

"Your brain is constantly checking in with the rest of your body to find out how you're feeling," says Kelly McGonigal, PhD, a health psychologist at Stanford University. "When your posture is erect, the message it gets is: I feel good about myself." One study, published last year in the European Journal of Social Psychology, found that subjects who sat up straight in their chairs instead of slouching were more confident about statements they wrote. Keeping your shoulders back and chest open also makes you look taller, slimmer, and radiantly self-assured.

Looking in the mirror

Be an Observer, Not a Judge

Don't issue good/bad/pretty/ugly judgments when you look in the mirror. Try to take in your physical attributes the way you would those of a child or beloved friend—with appreciation and acceptance, not criticism. "Studies using eye-tracking technology have shown that people who are unhappy with their appearance zero in on their perceived flaws when they look in the mirror," says Nancy Etcoff, PhD, director of the Program in Aesthetics and Well Being at Massachusetts General Hospital. Turn your gaze on the feature you like (we know you have at least one). "When your eyes take in something that pleases you, your brain's reward system is activated, lifting your whole mood," says Etcoff.

Woman compliments her friend

Say "Thanks"

Stop deflecting praise about your appearance. Simply say "thank you" when someone compliments your thick hair or sparkling eyes. You—and your admirer—will feel better about the exchange, creating positive reinforcement that makes you both want to give and receive compliments more often.

Bright blue scarf

Wear Color

Just a pop of color—say, in a necklace or scarf—can light up your face, and your mood. Not sure what to add to your wardrobe of black and greige? Try blue: "It's universally considered a 'happy' color, and there's a shade that looks good on everyone," says fashion stylist Joe Lupo, coauthor of Life in Color. If your skin tone is warm (it looks yellow-orange next to a piece of white paper), choose royal blues; if your complexion is cool (it has a more pinkish cast), try icier blues or aquas.


Shopping in a boutique

Loosen Up

"Body image can be externally influenced—by a number on a scale or an image in a mirror—but it's also affected by physical sensations like discomfort," says McGonigal. When you wear clothes in the smaller size that you want to be (or once were), the feeling of constriction sends a constant signal to your brain that you're not thin enough. This isn't an appeal for elastic waistbands but for clothes that are both elegant and comfortable—in the size you are now.

Lightbulb

View Yourself in a Flattering Light

We mean that literally, as in change your light bulbs. White-coated incandescent bulbs cast a wash of soft, pretty light, says lighting expert Dan Blitzer, president of the Practical Lighting Workshop. The Philips Natural and GE Reveal brands also filter out yellow tones for a clean white light that goes easy on all skin tones. Consider the placement of your light fixtures as well: "When light reaches your face from all directions, it minimizes lines and shadows," says Blitzer. In your bathroom, replace overhead lighting with fixtures on either side of your mirror.

This story originally appeared in the January 2010 issue of O, The Oprah Magazine.

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