1. For a few days? Don't look in a mirror. You can tell without one if your pants or shirt are buttoned, and you can be as presentable as need be just by brushing your hair and teeth, washing your face, all without a mirror.
2. Wear comfortable clothes, only, for a week, think of your comfort, of what colors and fabrics please YOU.
3. Next time you find yourself obsessing on the look of a given body part? Stop yourself, and instead, think of all the things that given part can DO. If you're prone to compare your parts to others by how they look, and can't stop comparing, perhaps try and switch to comparing or admiring what others body parts can DO. For instance, Jackie Joyner-Kersee's legs can run faster and harder than I know mine can. My great-grandmother's arms built a whole BARN.
4. Cook. Seriously, take the time to do it. Enjoy chopping, the smell of fresh foods and spices, of creating something tasty and wonderful. Try a recipe for something you love but have never cooked yourself before.
5. Swap out your body image problems. have stright hair but want curly? have big breasts but want small ones? Are short but want to be tall? Pick a friend who has what you covet, and share both your gripes. Listen to them with a keen ear for where they're coming from: are they really about comfort and functionality, or are they about what the world tells each of you is or isn't desireable?
6. Tune out the crap for a week. If you read beauty and fashion mags religiously, take a break. If you watch a lot of sitcomes, mainstream films, tune out and choose more diverse and real media.
7. Add it up. Sit down and really figure out how much time and money you spend on your body and appearance as opposed to other things: hobbies, friends (when you aren't all spending money on appearence-based items), time with partners, your home, room or pets, things that meet like goals like a college savings or money to travel, books, music, exercising for health and enjoyment, getting outside.
8. Just the facts, ma'am: take a real look at facts about size, appearance, health and lookism. For instance, the average weight of a model is 23% lower than that of an average woman; 20 years ago, the differential was only 8%, less than 5% of women naturally possess the body type displayed in advertising, and the average adult American woman weighs 144 lbs. and wears between a size 12 and 14. If shop mannequins were real women they'd be too thin to menstruate. Each year the U.S. spends over $33 billion on weight-los programs, fad diets, diet foods and drinks. New York's budget for public education is less than that. More than 80% of 4th grade girls have been on a fad diet. 95 percent of diets? Fail. If the average male model had the same proportions as the average female model, he would be 6'5" and 160 lbs. The average woman is exposed to around 1500 ads daily, and spends at least one hour a day on nothing but her appearance. A psychological study in 1995 found that 3 minutes spent looking at models in a fashion magazine caused 70% of women to feel depressed, guilty and shameful. 50% of American women are dieting and 75% of "normal" weight women think they are too fat: 45% of underweight women think they are too fat. The amount spent by women on cosmetics every year could buy 3 times the amount of day care offered by the U.S. government, 2,000 women's health clinics or 33,000 battered-women's shelters.
(By all means, add to the list with your own ideas.)