Michael Bloomberg, the billionaire mayor of New York City, was asked by a caller to his radio show this morning to share his personal formula for success.

Among his more interesting recipe items? Limiting bathroom breaks to avoid leaving your desk, and picking up garbage from the street.

Here, in full, are his words of wisdom:

1. Work hard—really hard.

“Everybody’s got different opportunities in front of ’em, different skill sets they bring, and luck plays a part of it. But my experience is that you make your own luck. The harder you work, the luckier you get.” “I always tried to be the first one in in the morning and the last one to leave at night, take the fewest vacations and the least time away from the desk to go to the bathroom or have lunch. You gotta be there. I mean, everybody says, ‘Oh, that’s crazy!’ But if you want to succeed … you can’t control how lucky you are, you can’t control how smart you are, but you can control how hard you work, so that’s the first thing.”

2. Take risks. Be persistent. Beware social media.

“Take risks. If you’re scared to take risks, you’re just gonna fit in with the crowd and never break average and probably won’t even make average,” he warned. “You’ve gotta have the courage of your convictions and be persistent. That’s not to say when you make a mistake, after a while, you gotta say, ‘I made a mistake.’ Admit it and change. It’s stupid to keep doing the same thing.” “But you can’t panic the first time somebody says something against what you’re doing and particularly in the days of social media. That’s really dangerous. Elected officials, they try one thing, and all of a sudden they get 10 zillion emails, tweets and whatever. Yeah, it’s one kid with a computer who wrote all of them, changed the name on every one and the language a little bit. So you gotta have the courage of your convictions and be persistent.”

3. Keep learning, seriously.

“Don’t ever stop learning. I dislike this concept of proficiency in education. … I’ve never met a Nobel Prize winner who didn’t think they had an awful lot more to learn and wasn’t studying every single day. So when a parent says, ‘How much does my kid have to learn before they can stop studying?’ I don’t know how to break this to you, lady or sir. There is no answer to that.”

4. Karma.