Maybe you're in a job you don't love, or maybe you're struggling with some extra pounds you can't shake--but chances are, there's a part of your life that's leaving you less than satisfied. The good news is that it's never too late to change things for the better. The key? Envisioning the life you want and figuring out how to make it happen--almost as if you're creating a business plan for your life, says Heidi Grant Halvorson, PhD, of Columbia University Business School.

Ready to have the life you want? Here's how to do it in seven steps:

1. Imagine. Most of us think that if we're attractive, smart, nice, or hard-working, our lives will magically turn out the way we want. But it's hard to create the life you want if you never consciously imagine what that life looks like. So think about where you want to be in one, five, or 10 years, and write it down.

More from Prevention: 20 Small Changes for a Healthier Life

2. Dream big. "No one ever sets out to lose 5 pounds and loses 20," says Halvorson, who cowrote the book Succeed: How We Can Reach Our Goals. When you set the bar high, however, your unconscious brain detects a big difference between where you are now and where you want to be and "throws resources at it," she says, like attention, effort, and memory. More mental resources mean a higher chance of success.

3. Stuff is rarely enough. While you can use goal-setting to, say, save up for a car, research shows that self-oriented goals, such as fame and fortune, don't create true, lasting happiness. Instead, Halvorson says, we need to pursue goals that satisfy three basic human needs: relatedness to other people, a sense of competence, and the autonomy to make decisions about our lives. So instead of imagining a shiny new BMW in your garage, imagine how can you create community in your life, do what you feel good at, and gain control.

4. Be realistic. If you think it's going to be easy, it won't be. People who are confident that they will succeed and equally confident that success won't come easily put in more effort, plan how to deal with problems before they arise, and persist longer in the face of difficulty. And--shocker!--these people are more likely to succeed than people who give up early.

5. Be specific. "I'm going to exercise" isn't nearly as effective as "I'm going for a walk Mondays, Wednesdays, and Fridays from noon to 1." Over 100 studies, Halvorson says, have shown that simply deciding where and when to do certain things can double or triple your likelihood for success. Having a specific goal creates a link in your brain between the cue ("it's noon") and the behavior that follows ("I'm going for a walk").

More from Prevention: Little Things Connected Couples Do

6. Assess. People who are really good at achieving their goals check in with their goals on a daily or weekly basis, often by writing in a journal just before bed. If they've met their goals, they rest easy. If they haven't, they make adjustments. "It's not enough to just monitor progress," Halvorson says. "Ask yourself, 'What am I doing right, and where am I going wrong? Do I need to seek advice or guidance from experts?'" More often than not, success means changing strategies along the way to adapt to opportunities or obstacles you didn't plan for.

7. Zip it. Talking about your goals to others can actually decrease the chances you'll succeed at them, because you give others the chance to denigrate your dreams. Also, some people actually slack off on goals once they've told others about them. "Research shows that people can get a certain satisfaction out of just saying that they are going to do something great, and it reduces their motivation to actually do anything," Halvorson says. So keep your goals, and keep them to yourself.

More from Prevention: Women Speak Up About Health Fears and Goals