It took just six months at her first job after graduation before Deanna Stephan, 24, realized it wasn't for her.

But it took another year and a half before she made it out, ditching the New York nonprofit scene to pursue her dream of becoming a teacher.

At least she did it. A lot of young workers hesitate to make such big changes, afraid of how parents, friends and potential employers will judge them for jumping ship.

That judgment isn't always fair. Patricia McDonald, a career and life coach in New York, says that job hopping is normal among young workers. Your twenties are an "exploratory decade," she said. "You're not supposed to make big decisions."

But that doesn't stop us from trying. Often, she said, young workers just "can't stand the tension of not knowing." So they close their eyes and commit to something new without really thinking. "A lot of bad decisions are made that way."

Indeed, it can often put you in situations even more miserable than the one you escaped from. Of course, there's no way to guarantee that won't happen, but there are a few steps you can take to make it less likely.

Abby Wilner, co-author of "The Quarterlifer's Companion," said it's important to understand the source of your unhappiness. "Is it external, from the tasks you are assigned or the people you work with, or is your unhappiness internal? Because if you are depressed or experiencing difficulties transitioning to life in the 'real world,' those feelings of isolation and instability can make everything seem worse, including your work situation."

Job hopping is normal, she said, but you should still be cautious and make sure that you're moving on for the right reasons, so your next situation will actually be an improvement.

Barry K. Zweibel, a career coach in the Chicago area, suggested that recent grads who find themselves changing jobs a lot spend an afternoon with their resumes, evaluating what they liked -- and didn't like -- about each position. They should consider job content, opportunities, how well their personalities fit, what the bosses were like, company size, supportive technologies and compensation. If they notice patterns, he said, they should use that realization to evaluate their next potential move.

Stephan did her homework, making sure she understood what she was getting herself into. It definitely helped that her mother had already worked in the school system for many years, as a teacher's aide.

Once she was confident in her choice, Stephan began researching options for switching to a teaching career. She looked at various graduate programs and Teach for America, before signing up to become a substitute teacher back in her home town of Reading, Pa. In a few months, she expects to start taking classes to earn her formal certification.

She calls her mind-set during the interim between when she realized what she wanted to do and when she actually made the jump one of "aggressive patience." To her, that meant keeping her focus on her goal, while remembering it wouldn't happen overnight. When one potential path to her goal would close, she would find and pursue another one.

Even when you think you know what you want, it can be tricky to decide a reasonable amount of time to stay at a job.

Mostly it depends on just how bad the situation is. And remember, it may not be the entire field that's a bad fit -- it may be a particular job or supervisor.

If the job is making you physically ill, quit as soon as possible, Wilner said. But if you're just bored and unfulfilled, try to stick it out for a year. Use that time to research other possibilities and weigh your options. Once you're confident in your decision, the next step will be convincing potential employers that you're not going to flake out on them.

It won't be as hard as you fear, Zweibel said. Employers realize that people leave jobs for many reasons. "You can explain that away one or two times."

And if this new job doesn't turn out to be the one? Keep looking.

Zweibel likened the search for one's ideal career to the surprise in a box of Cracker Jack. "Sometimes it's at the top of the box, sometimes it's at the bottom." You never know how long it will take you to find it.

Tales of the Unexpected

Have you ever had a job where the workplace culture turned out to be radically different from what you expected? Perhaps you had trouble fitting in? If so, tell me how you handled it. Send your stories to slayterme@washpost.com.

Join Mary Ellen Slayter at 2 p.m. Sept. 26 for Career Track Live, an online discussion of issues affecting young workers, at www.washingtonpost.com/wp-dyn/liveonline/jobs/careertrack.