After decades of working in the fashion industry, including eight years at luxury fashion brand Burberry, Angela Ahrendts decided to take a leap into a completely different field: tech.

In 2016, she became a member of the Apple executive team as senior vice president of retail and online stores.

The jump wasn't the most comfortable, Ahrendts said at World Business Forum in New York City.

"You get incredibly insecure in that first month or so," she said. "You focus on everything you don't know, and you get so overwhelmed."

But then Ahrendts had a realization: she wasn't hired to know more or even as much as other employees. Ahrendts was hired to bring something new to Apple, something others at the company couldn't provide.

"It's not your job to know," she said. "It's your job to connect, it's your job to enable. Putting together a whole different framework, bringing groups together," is what she was there to do.

It's easy to feel lost or underqualified when starting at a new position, especially if you switched industries. Here's how to combat the imposter syndrome and negative self-talk that often comes with a career pivot.

Question your thoughts

To curb negative thoughts about your capabilities, be mindful about what prompts these intrusive ideas, Judy Ho, a neuropsychologist and professor at Pepperdine University, told CNBC Make It.

"Just notice where those patterns are, and what situations trigger you and you're going to start finding a theme," Ho said.

Then, questions your thoughts. Ask yourself what evidence supports the idea that you are incapable of doing this specific job, and what evidence contradicts it. Perhaps you don't know everything about the industry, but you are a good team leader, have a proven track record of increasing revenue, or are an efficient multi-tasker.

Write down your findings in two columns and compare them. Oftentimes the evidence demonstrates that you do, in fact, bring a lot to the table, Ho said.

This exercise can also help you remember that these thoughts aren't fact.

"Know that thoughts are not the absolute truth," Ho said. "There's no way that you have tens of thousands of thoughts and that they're all true."

By being critical of the stories you tell yourself, you can quell any anxieties you might have around being the rookie in the office.

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