Richard Branson's mom taught him this valuable lesson that's crucial to his success

Greg Doherty | Getty Images. This mindset has helped Richard Branson become a billionaire.

Sixty seven-year-old billionaire and entrepreneur Richard Branson has done a lot of crazy things. He left school at 16 to start a magazine, tried to circle the globe in a hot air balloon and is now expecting to go to space by April of 2018. His brand, Virgin Group, has 60 businesses , ranging from mobile phones to airlines. He says his greatest inspiration throughout it all, has been his mother. Rather than squash his wild ideas, she encouraged them. "Your father and I ... opted to give you plenty of scope to learn by your mistakes and so left you to get on with your Christmas tree growing, bird breeding and all the other weird and wonderful enterprises you came up with," Eve Branson writes in a letter to her son "Ricky" that Branson shared on his blog. But, there was one thing that she stood firm on, and Branson says it taught him a crucial skill for success: how to treat other people . "The most important skills I had to learn to be successful were people skills," he tells CNBC Make It.As a kid, his mother emphasized the importance of respecting others. "If I ever said anything ill about somebody as a kid, my mum would send me to the mirror and make me stand there for 10 minutes because she said it reflected so badly on me," Branson says.That lesson had a huge impact on Branson's leadership style."I think that upbringing taught me never to say ill about anybody, always to look for the best in people, and I've found ever since that by looking for the best in people — you get the best," he tells CNBC Make It. "I think for a leader, it's absolutely critical that that's how you conduct your life."For Branson, his mom has been worth listening to all of these years. "My mother, Eve, is my biggest inspiration, my most encouraging champion, and my greatest sounding board," he writes on his blog . "Thank you mum for motivating me each and every day on my life; for teaching me that not even the sky's the limit; and that impossible is just a word." Don't miss: Billionaire Richard Branson: This skill set is the most critical to achieving success Like this story? Like CNBC Make It on Facebook . Sixty seven-year-old billionaire and entrepreneur Richard Branson has done a lot of crazy things. He left school at 16 to start a magazine, tried to circle the globe in a hot air balloon and is now expecting to go to space by April of 2018. His brand, Virgin Group, has 60 businesses , ranging from mobile phones to airlines. He says his greatest inspiration throughout it all, has been his mother. Rather than squash his wild ideas, she encouraged them. "Your father and I ... opted to give you plenty of scope to learn by your mistakes and so left you to get on with your Christmas tree growing, bird breeding and all the other weird and wonderful enterprises you came up with," Eve Branson writes in a letter to her son "Ricky" that Branson shared on his blog. But, there was one thing that she stood firm on, and Branson says it taught him a crucial skill for success: how to treat other people . "The most important skills I had to learn to be successful were people skills," he tells CNBC Make It. As a kid, his mother emphasized the importance of respecting others. "If I ever said anything ill about somebody as a kid, my mum would send me to the mirror and make me stand there for 10 minutes because she said it reflected so badly on me," Branson says. That lesson had a huge impact on Branson's leadership style. "I think that upbringing taught me never to say ill about anybody, always to look for the best in people, and I've found ever since that by looking for the best in people — you get the best," he tells CNBC Make It. "I think for a leader, it's absolutely critical that that's how you conduct your life." For Branson, his mom has been worth listening to all of these years. "My mother, Eve, is my biggest inspiration, my most encouraging champion, and my greatest sounding board," he writes on his blog . "Thank you mum for motivating me each and every day on my life; for teaching me that not even the sky's the limit; and that impossible is just a word." Don't miss: Billionaire Richard Branson: This skill set is the most critical to achieving success Like this story? Like CNBC Make It on Facebook .

More From CNBC