4. Set small, realistic goals. A handful of studies have demonstrated that those instructed to make small changes, like sitting up straighter, were able to raise their scores on lab tests for self-control. While the research isn't conclusive, setting small goals makes sense from a more-likely-to-succeed perspective. Whatever goal you set for yourself, cut it in half, McGonigal recommends. If you vow to lose 30 pounds, shoot for 15. Set a goal to exercise once or twice a week instead of every day if you're just starting to work out. "Setting small goals will give you small successes that will motivate you to continue," she explains. Also, you need to anticipate failure (like gaining a pound after you've lost two), so you don't end up getting derailed.
5. Don't get too hungry—or too sleep-deprived. Feeling famished lowers your willpower, according to Florida State University researchers who found that those who had low blood glucose levels from not eating performed worse on self-control tasks than those who were satiated. Same goes for those who sleep less than six hours a night. "They're much more susceptible to giving in to cravings," says McGonigal. "Sometimes the answer to getting more willpower is to just sleep a little more." And be sure to eat every four hours during the day to keep your brain fueled with glucose.
6. Give it three weeks. Research suggests it takes about 21 days of following a new behavior—whether it's going to the gym or avoiding alcohol—to establish those brain connections that make a new routine feel, well, old. "For some people it could be 21 days, for others 15, or for others 30," says Kober, "but what's clear is that the more often you practice a different activity, the more likely you are to repeat it." You should also be aware that one slip-up doesn't mean you've failed. Taking one drink after you've been sober for months, she adds, doesn't automatically set the brain back into a pattern of alcoholism.