The first British woman to climb Everest said that people who know what they want to do from a young age are lucky. Here's her best career advice.

• Rebecca Stephens was the first British woman to summit Everest, and climb the Seven Summits.
• Despite her success, she said she didn't know she wanted to do while growing up.

It is easy to look at high achievers and think that they've always had a plan about what they wanted to do with their career.

Rebecca Stephens could fall into that camp. In 1993, she became the first British woman to summit Mount Everest. She followed it up by becoming the first woman to climb the "seven summits," consisting of the highest peak on each of Earth's seven continents.

Stephens, who is the author of the book "Making It Happen: Lessons from the Frontline of Strategy Execution," told Insider that people who have a clear idea of what they want to do from an early age are lucky. Despite her success climbing mountains, she said she didn't know what she wanted to do while growing up.

After graduating school, Stephens worked for a few years as a journalist. But she only discovered her love of mountains in her late 20s after she was invited to cover an expedition to the Himalayas for a magazine.

"It was only on Everest that I had absolute conviction of what I wanted to do with no wavering this way or the other," Stephens told Insider.

Even then, it took her a few years to leave her job and gather funding for an expedition to climb Everest.

"It was bloody terrifying," Stephens said. "People talk about the risk on the mountain, but for me, what I saw was the biggest risk was giving up a job and in a recession with a mortgage to pay."

Stephens admitted that she was lucky in many ways. She didn't have any wider caring responsibilities, could rent out her flat while away on an expedition, and was handed the opportunity.

But she said there is a wider lesson for people early in their careers, for whom there can be a temptation to follow expectations and go into jobs because they think their parents want them to. Instead, if they want to find fulfilment, they should listen to their "inner voice."

No career path is ever totally smooth and many highly successful people have started out in different fields before changing careers later on.

Jeff Bezos, for example, had several jobs on Wall Street before launching Amazon aged 31. Likewise, Donald Fisher the founder of the Gap Store had no prior retail experience before opening his first store aged 40.

Stephens has some advice for anyone still trying to find their calling. "Don't panic. It's OK to explore. It's OK to try different things," she said.

But there is a balance. While it's important to think about your career, don't overthink it to the point of procrastination, Stephens said.

There is a point when you have to jump in with both feet, she said, adding that sometimes you'll also need to take a job for security.

"It's a question of finding the sweet spot, '' Stephens concluded. "But quite often if you follow what it is that really fulfils and interests you, the rest falls into place."