Distract Yourself
Put on music and dance, scrub the bathtub spotless, whatever engrosses you—for at least 10 minutes. "That's about the minimum time needed to break a cycle of thoughts," says Nolen-Hoeksema, who's been studying rumination for more than 20 years. Or choose something to focus on. "A friend told me that she once started counting the number of times the speaker at her conference said 'like,'" Nolen-Hoeksema recalls. "By the time he finished, she'd stopped ruminating."

Make a Date to Dwell
Tell yourself you can obsess all you want from 6 to 7 p.m., but until then, you're banned. "By 6 p.m., you'll probably be able to think things through more clearly," says Nolen-Hoeksema.

3 Minutes of Mindfulness
For one minute, eyes closed, acknowledge all the thoughts going through your mind. For the next minute, just focus on your breathing. Spend the last minute expanding your awareness from your breath to your entire body. "Paying attention in this way gives you the room to see the questions you're asking yourself with less urgency and to reconsider them from a different perspective," says Zindel Segal, PhD, co-author of The Mindful Way Through Depression.

The Best and Worst Scenarios
Ask yourself…

"What's the worst that could happen?" and "How would I cope?" Visualizing yourself handling the most extreme outcome should alleviate some anxiety, says Judith Beck, PhD, director of the Beck Institute for Cognitive Therapy and Research in Bala Cynwyd, Pennsylvania. Then consider the likelihood that the worst will actually occur.

Next, imagine the best possible outcome; by this point, you'll be in a more positive frame of mind and better able to assess the situation more realistically.

Call a Friend
Ask a friend or relative to be your point person when your thoughts start to speed out of control.

How to Move On
Say, "Oh well."

Accept that you're human and make mistakes—and then move on, says Dr. Beck. Be compassionate. It's harder than it sounds, so keep practicing.