A former GE and NBC exec who never got her MBA spent the first 90 days as an exec reading textbooks and embracing what she didn't know

Hollis Johnson/Business Insider

Beth Comstock is the author of memoir and career guide "Imagine It Forward."

• When Beth Comstock was hired as chief marketing officer for General Electric, she spent her first 90 days on the job learning about the basics of marketing.
• Comstock picked up Phil Kotler textbooks, read "The Four Ps of Marketing," and hired people with the expertise she needed to teach her marketing.
• She valued feedback and asked for help where she needed it. She said employees who act like they know everything will eventually get called out.

When Beth Comstock was hired as chief marketing officer for General Electric, she spent her first 90 days on the job learning about the basics of marketing.

Comstock reached the C-suite by taking one day at a time and overcoming her shyness, she shared on an episode of Business Insider's podcast "This Is Success." She spent 27 years at General Electric and former NBC properties, eventually rising to the level of former vice chair at GE. She recently wrote a memoir and career guide "Imagine It Forward."

When Comstock was hired as CMO, GE hadn't had a marketer in 20 years, she said. Without an MBA or any business schooling, she spent the first three months as CMO learning the in's and out's of her job.

"So it's a very vulnerable moment to say, 'I don't know this.' But clearly, I was put in the job because they saw something else," Comstock said. "So I had to also say, 'I'm here for a reason. Don't try to be a business school person, because you didn't go to business school.'"

Read more: A former GE and NBC exec says being introverted isn't the same as being shy, and she wasn't successful until she figured out the difference

To prepare, Comstock picked up textbooks by marketing consultant Philip Kotler, read "The Four Ps of Marketing," and hired people with the expertise she needed to teach her marketing. She said most employees at GE saw marketing as the advertising department, which is what Comstock was doing at the time.

"So frankly, it wasn't like I was filling some other job," she said. "No one really knew what marketing could be. So it was a clean slate, in some respects."

Even though Comstock grabbed the CMO position by the horns, she asked for help when needed and valued feedback. As a self-proclaimed introvert, Comstock said it took her time to open up to others when asking for guidance.

"People were very generous, and some people didn't have time for me and you find the ones who do," Comstock said. "So you have to ask for help. You cannot go into these situations and go, 'No, I'm going to act like I know everything,' because you'll get called out."

Listen to the full episode and subscribe to "This Is Success" on Apple Podcasts or Art19.

Get the latest General Electric stock price here.