Want a job at Facebook? Here's how to get one

We thought a new haircut, a quick polish of your smart shoes and a suit is all you need to impress at a job interview.

Not according Facebook CEO Mark Zuckerberg who says there's just one test he uses for potential employees.

The billionaire would only hire someone he himself would want to work for.

If we were starting a business at the age of 19, we'd probably hire a few more experienced minds to help us out too.

So far, it seems the test has served the billionaire entrepreneur well.

He employed Sheryl Sandberg as his chief operating officer and now considers her a mentor.

Facebook has more than a billion users but its workforce is relatively small, with fewer than 10,000 people employed by the company.

That compares to tech giant Google which has almost 54,000 employees.

Even though we doubt Zuckerberg interviewed all 10,000 of his workers, the test has made the 30-year-old one of the most successful businessmen in the world.

But the billionaire told the Mobile World Congress in Barcelona the most important thing when looking for a job is to "just have faith in yourself and trust yourself".