As soon as billionaire entrepreneur Mark Cuban wakes up in the morning, he starts learning. For him, that means spending the entire first half of his day reading. He says its been key to his success.
"I read everything I can. I don't care what the source is," Cuban tells CNBC Make It. In total, he says his reading routine takes up "four to five hours a day."
Here's where Cuban says he is investing his time.
Cuban subscribes to a mix of local and national news outlets, both for the digital and print editions.
"I start my days with the newspapers," he tells CNBC Make It. He subscribes to the Dallas Morning News, The Economist, The New York Times, The Wall Street Journal, The Washington Post and six magazines, Cuban tweeted in August.
He also browses curation sites like Techmeme and Memeorandum.
After he's caught up on the news, Cuban turns to his email. As an investor on ABC's "Shark Tank," and owner of the NBA's Dallas Mavericks, Cuban has a lot of businesses to keep up with. His portfolio of investments includes dozens of ventures, in every industry from movie theaters and e-sports to health conscious cookies.
To keep track of it all, Cuban prefers to communicate over email instead of having meetings.
"No meetings or phone calls unless I'm picking up a check. Everything is email, Cuban told Thrive Global in 2016. "Saves me hours and hours every day. No meetings. No phone calls. All because of email."
Reading through his emails in the morning takes, "about an hour," Cuban told fellow "Shark Tank" investor Daymond John in January.
Once his emails are taken care of, "[It's] newsletters and whatever I'm focused on educating myself about tech-wise," Cuban tells CNBC Make It. Right now, he's studying up on, "all things AI, quantum and nano technology that I can."
Although Cuban is worth nearly $4 billion according to Forbes, he maintains that continuously learning new things is the only way to remain competitive.
"Particularly in the tech industry, the only constant is change," Cuban explained on "The Jamie Weinstein Show" podcast. "So you've got to stay up, because otherwise, there is some 12- or 18-year-old kid that is coming in with a better idea to kick your a--."
Cuban has been a voracious reader since he got started selling computer software in Dallas in his 20s, when he would take home programming manuals and read them at night.
"A guy with little computer background could compete with far more experienced guys just because I put in the time to learn all I could," Cuban wrote on his blog. "Most people won't put in the time to get a knowledge advantage.
"To this day, I feel like if I put in enough time consuming all the information available, particularly with the net making it so readily available, I can get an advantage in any technology business."
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