Starting a business after an established career in another field might seem daunting. Career change, however, is actually the norm now. The Bureau of Labor Statistics reports that Baby Boomers held an average of 12.3 jobs between the ages of 18 and 52. Most of those job changes occurred before the age of 24, but in reality, 93 percent of jobs don't last five years. Millennials are even more likely to change jobs or careers than their predecessors. 

So what happens when you get a few years into a career and decide it's not right for you after all? "A job change can be scary, and changing careers or starting a business is even more intimidating," says Kelly Hyman, who left a successful acting career to become a class-action attorney. "But the biggest hurdle is in your head."

Don't let fear and apprehension hold you back. Here's how you can make the shift.

Embrace Career Change as the Norm

The era of working in one office for 50 years for a pension and a gold watch are over. Boomers have known for decades that Social Security would eventually fall short. They've already been downsized and laid off during recessions. Those same recessions drained their pensions and real estate assets of value. The labor force today isn't expecting longevity or employer loyalty, and employers aren't hiring for life.

"Many of my clients should expect to have four to seven careers in their working lives," says Mary Lindley Burton, the founder of Burton Strategies and the author of In Transition who's helped people through career transitions for more than 30 years. "People focus on the contribution they can make to a company, but they are not thinking of a lifetime commitment.

Think of a career that will satisfy you for five to 10 years. That's long enough to justify investing the ground-level effort. Your goals may change in the next decade, and avoiding planning an entire career around one move can prevent you from feeling stuck.

Don't Be Afraid to Do a 180-Degree Turn

On the spectrum of career choices, acting and law seem like they couldn't be further apart. But Hyman said making the change wasn't as dramatic as you might think; she was able to pull skills from her acting career to help her in law. 

"Those acting skills come in very handy in the courtroom," she says. "I came into this profession already trained to emote, enunciate, project, carry confidence and engage the audience." Don't shy away from big changes--think of how your skills or perspectives might transfer to another field. A detail-oriented banker, for example, might thrive in a data analysis role; a connection-driven teacher could make a great keynote speaker.

If a simple change in jobs or departments isn't enough, don't be afraid to completely change fields or go into business for yourself. Remember that everything you've done to this point has not only fueled your interest in the next step, but it's also prepared you for it. Take an inventory of what you can bring to the table--this can help you determine how to shore up your weak spots and move forward.

Think Carefully About Returning to School

There's no age limit on learning, so going back to school is always an option. But that doesn't mean it's the best option. The average debt load is $25,000 for a bachelor's degree and $45,000 for a master's, and over a third of graduates with student debt say it wasn't worth it, according to Pew research.

A degree is necessary in some fields, like medicine or law. But a medical practice also helps graduates generate the income to pay off their student debt. If you're going back to school, do the math first. Be very realistic about what you're likely to make. Ask yourself honestly whether it's enough to justify the cost of a degree. 

Steven Pearlstein, an economics columnist at The Washington Post and the Robinson professor of public affairs at George Mason University, says it's true that too many college courses are focused on specific knowledge students won't ever use instead of critical thinking. "The idea that a traditional college education is right for everyone who reaches age 18, or that it is necessary for getting a good job or achieving success in life--that is simply wrong," he says.

If you can make your career change or launch your business without going back to school, do it. Apprenticeships or certification programs may get you the knowledge you need. And many employers value life experience and work experience--even in unrelated fields--as much as formal education. An HR friend once told me that she so highly values the work ethic instilled by waitressing that she throws out résumés that don't include a service industry position. Your experience might be more valuable than it seems.

One of the biggest benefits of starting fresh after having had a career is getting to see the world from a completely different angle. If the voice inside your head is telling you a career shift or new business venture is necessary, but also reckless or irresponsible, remember how normal it really is. Focus on the positive; people do this all the time with great success. There's no reason you can't do the same.