Billionaire Ray Dalio believes in an old saying: "When the student is ready, the teacher will appear."

That may explain how Dalio, a hedge fund tycoon with a net worth of $20 billion, according to Forbes, became a mentor to entrepreneur and music mogul Sean "Diddy" Combs.

The two met during a photoshoot for Forbes magazine's list of "100 Greatest Living Business Minds" in 2017 when Combs approached Dalio and started asking him questions, Dalio tells CNBC Make It.

"I didn't really know who he was," Dalio says.

But their meeting turned into a sustained relationship — as Dalio tweeted in 2019, a mentorship aimed at helping Combs "take his great success to another level."

But you don't have to be a household name like "Diddy" to score a great mentor, says Dalio. Instead, some personality traits are key to establishing a strong mentor relationship, he says.

"The first thing that it starts with is humility," Dalio says. For him, that means approaching a prospective mentor and saying something like: "I'm worried that I don't know the best [next move], and I really do want to learn."

As for finding people who can help you grow, Dalio says, you may already know them. Think about the people in your life who you admire and who already know and care for you.

You also don't need to designate a single person as your "official" mentor. Rather, Dalio says, find different people who can help answer questions or provide advice across various parts of your life. The only prerequisite is that you be open to their ideas and suggestions.

Why their unconventional partnership works

In one of their mentoring sessions, Combs told Dalio that he wanted leadership advice because his team wasn't living up to his "very high" level of excellence, according to a video Dalio posted in 2019.

In response, Dalio says, he reminded Combs that he is "captain of the team" and that "whatever you want in your life, you have to ask, 'Who is gonna be capable of giving that to me?'"

Dalio says he also spoke to Combs about his concept of "radical open-mindedness," which is the ability to analyze different points of view without letting your ego, blind spots or weaknesses get in the way.

In a statement to CNBC Make It, Combs praised Dalio's mentorship and friendship.

"He is one of the most successful people in the world, and I look forward to continuing to learn from him for many years to come," Combs says.

At face value, Combs may not seem like someone who needs a mentor. The 51-year-old has turned his music talent and entrepreneurial acumen into a fortune worth $740 million, according to Forbes. His ventures include record label Bad Boy Records, bottled water brand AQUAhydrate, clothing company Sean John and alcohol business Combs Wine & Spirits.

But Dalio, 72, says he happily agreed to mentor Combs — particularly after learning how the rapper initially found success.

Combs was born in Harlem, New York, and raised by his mother after his father was murdered in 1974. "My father was a drug dealer," Combs told Revolt, a television network he founded, in 2013. "So I learned early in life that there [are] only two ways out of that."

Combs said he chose to hit the books instead of following in his dad's footsteps.

"[H]e's a real hero," Dalio says. "And he wants to be a role model and help others."

That ethos clearly resonates with Dalio, who stepped down as co-CEO of hedge fund Bridgewater Associates, a company he launched from a two-bedroom New York City apartment, in 1975. Since then, Dalio has spent much of his time building Principles, a people management software company that he says is designed to help share his decades of knowledge with younger generations. Its latest iteration, PrinciplesUS, launched on Tuesday as a personality assessment tool for corporate teams.

The bottom line, Dalio says: "If you're receptive and you look and you listen, [the right mentors] will come."

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