"If you look for the best in people, if you motivate people, if you praise people, if you don't criticize people — these are all the skills that are needed to be a great leader," he explains.
In order to develop solid interpersonal skills, paying attention is key.
"You need to be a great listener as well," Branson tells CNBC Make It. "[I] hate hearing leaders just pontificating their own views and not listening to other people."
The last step: "You need to write down what you hear from other people," he adds. Branson espouses the value of taking notes and attributes some of his best ideas to having a pen and paper available.
Even Elon Musk has heard this advice from Branson. In Branson's new book, "Finding My Virginity," the British billionaire recalls a time vacationing with Musk on Necker Island, way before Musk was founder and CEO of Tesla and SpaceX and worth $20 billion. At the time, Branson, who was impressed with Musk's technical knowledge, told him, "If you don't have your own ventures one day, you're welcome to come and run one of mine — just brush up on your people skills," Branson writes.
In his own companies, Branson tries to build a culture that focuses on employees.
"The key to success in business is all about people, people, people," he writes on his blog. "It should go without saying, if you look after your people, your customers and bottom line will be rewarded too."
When it comes to investing in new businesses, Branson is also thinking about people first. To him, the big picture is more important than the details.
"What I am good at is coming up with interesting ideas and then finding amazing people to turn them into reality," he writes in the book. "I see investing in start-ups the same way. I'm not always caught up in the details of what a particular app will or won't do; I'm more interested in the personalities behind the companies, and the purpose within their visions."
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