Mike Bloomberg, the CEO of Bloomberg LP and former New York mayor, has had his fair share of success.

At the age of 73, he has become the 14th richest man in the world with a net worth of $US40.7 billion (£26.6 billion). He is a completely self-made billionaire.

However, when he was in London on Thursday at a Goldman Sachs’ event in aid of small businesses, his advice was pretty harsh for anyone that wants to get ahead.

Appearing on the stage with Goldman Sachs’ investment banking co-chief Richard Gnodde, Bloomberg delivered six key pieces of advice for entrepreneurs — and they weren’t for the thin-skinned.

Keep perspective

“I’ve never had a bad job. I’ve only ever had two bad days in my life — when my mother died and when my father died. Apart from that, how bad can it be?”

As long as you’re alive and your family are alive, suck it up.

Work hard

“If there’s only one key to success, it’s hard work. I always give the most difficult and complicated assignment I have to the most overworked person in the company. There’s a reason they don’t have time — work is a marketplace and it’s telling you this person is good.

“When I worked at Salomon Brothers, I was always the first person in the office in the morning. The second was Barney Salomon, the managing partner. So if he wanted to know the football scores or if he needed a match for his cigar, then he’d come over and talk to me. All it was, was coming in early. If you like what you’re doing it’s fun, if you don’t it’s miserable.”

Take working hard to the next level. Get in early, leave late, and and go further than your competitors.

Have realistic goals

“None of you are going to be Mark Zuckerbergs. It’s just not going to happen.”

In other words — manage your expectations and don’t dream about the first billion.

Love what you do

“It must be miserable to wake up everyday and hate what you do. Go and do something else. If you hate it, how can it be worse?”

You’ll never be great at something if you don’t like doing it.

Thrive in adversity

“If you say, ‘oh last week I cured cancer, two weeks before that I wrote the great American novel and last month I brought peace to the Middle East’ — my eyes glaze over.”

“But if you say ‘look, my father never existed, my mum had cancer, I’m working five shifts at McDonald’s’ — that’s the person I’m going to hire.”

As a self-made man, Bloomberg prefers drive and hard work over academic achievements in his employees.

Be genuine

“There is a characteristic that all good leaders have and it’s that they’re genuine. Will this person be with you in the trenches, go over the top, or will they stay back and say ‘you go’?”

Bloomberg’s speech may be harsh and direct but at least it’s genuine.

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