Richard Branson dropped out of school at age 16 to start his first business, Student magazine.
Since then, the entrepreneur has built eight billion-dollar companies in eight different sectors and accumulated a fortune of approximately $5 billion.
If the 67-year-old lost all of his money overnight and had to start from scratch, he knows exactly what he would do: Start all over again as an entrepreneur, launching a new business he hasn't tried yet.
For starters, "I'd have to make sure I went bust in the most spectacular, exciting failure in history," Branson writes in his new autobiography, "Finding My Virginity." "Then I'd autograph lots of £10 notes and sell them (hopefully for more!)."
Branson, a devoted note taker, would then "go through all my notebooks, find the best ideas that had fallen through the cracks and start them up."
That strategy has worked for him in the past. The billionaire credits much of his success to the simple habit of jotting down ideas: "Some of Virgin's most successful companies have been born from random moments — if we hadn't opened our notebooks, they would never have happened," he writes on LinkedIn.
While a lot has changed in the business world over the past several decades, the fundamentals of building a strong business have not, Branson notes: "The principles are the same and still fit what I am good at: finding markets that need shaking up, coming up with ways to make people's lives better, then finding brilliant people to bring it to life.
"Once an entrepreneur, always an entrepreneur. I know I'd find a gap in the market somewhere."
He's not the only billionaire who is confident he could get back on his feet after a crisis. If Mark Cuban lost everything, he says he could succeed again and make at least seven figures.
"Knowing what my sales skills are and the products that I am able to sell, I think I could find a job selling a product that had enough commissions or rewards for me," he says on NPR's podcast, "How I Built This."
"Could I become a multimillionaire again? I have no doubt."
Like this story? Like CNBC Make It on Facebook!