Here's Mark Zuckerberg's one tip for hiring employees

Mark Zuckerberg mobile world congress 2015 barcelona

(David Ramos/Getty Images) Mark Zuckerberg speaks at Mobile World Congress 2015 in Barcelona, Spain. Over the past 11 years, Mark Zuckerberg has built a $200 billion company with more than 9,000 employees everywhere from Austin to Auckland, Washington D.C. to Warsaw. As of December 2014, Facebook sees almost 900 million daily users.

Zuckerberg has revealed his one rule for hiring at the Mobile World Congress tech conference held in Barcelona, the Telegraph reports. Here's what he looks for in an employee:

"I will only hire someone to work directly for me if I would work for that person... It's a pretty good test and I think this rule has served me well."

The Facebook founder also provided other tips on building a successful company. "The most important thing is to keep your team as small as possible," he told the audience, according to CNN. And "the most important thing is to just have faith in yourself and trust yourself... When you're young you hear that you don't have the experience to do things, that there are people with more experience than you. I started Facebook when I was 19."

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