14. Take Care of Yourself
Taking care of yourself could save you from career burnout, says Branson.
The Virgin Group entrepreneur wrote on his LinkedIn blog, "When I'm asked: 'What's the key to success in business?' my answer can differ depending on the subject at hand — delegation, people, learning from failure, etc. — but when it comes down to it, the key is you. The simple fact is, if you don't take care of yourself, you won't be able to take care of business."
Branson exercises every day, no matter where he is or what he's doing.
"A healthy body equals a healthy mind, and a healthy mind takes care of business," he said.