In 1994, J.K. Rowling hadn't yet introduced the world to Harry Potter or its magical dimension of butterbeer and owls. She wasn't an acclaimed author — in fact, far from it.
Back then, Rowling was a single mother, writing out chapters by hand in a cafe in Scotland while her infant daughter slept next to her. The pair were surviving on government benefits.
"I don't want to dramatize, but there were nights when, though Jessica ate, I didn't," says Rowling, referring to her daughter, in a 2007 Telegraph interview.
Today, Rowling has sold over 450 million copies of her seven Harry Potter novels. Those books have also given rise to a larger empire of spin-offs, theme parks and Broadway productions. In 2017, Forbes estimated her net worth to be $650 million.
And she's still writing. Currently, Rowling is working on the next book in the "Cormoran Strike" crime fiction series, which she writes under the name Robert Galbraith. When a fan asked Rowling on Twitter how the new book, "Lethal White," is going, she opened up about the process and revealed her writing routine.
When starting a new project, Rowling says she takes time to plan and organize her thoughts. For "Lethal White," she created "a vast, complicated, color-coded table showing all the suspects, with blue ink for clues and red ink for red herrings."
She still writes using longhand, then transfers her work to the computer.
"I like physically shuffling around with papers," she once explained to the Telegraph. She also prefers to work in coffee shops, where "You don't have to break off and go in the kitchen to make coffee," she told the paper.
Sometimes Rowling comes up with the idea for a new book while working on another project. For example, she had the idea for "Lethal White" in 2013.
But she remains dedicated to long-term thinking, iteration and improvement.
Rowling's forward-thinking mindset is shared by other wealthy and successful people. Amazon CEO Jeff Bezos, for one, tries to cultivate such thinking in his company.
"If you're going to invent, it means you're going to experiment, and you'll have to think long-term," Bezos says in a 2013 interview with Four Peaks TV.
Fellow billionaire Richard Branson agrees.
"On every adventure I have been on – whether setting up a business, flying around the world in a balloon or racing across the ocean in a boat – there have been moments when the easy thing to do would be to give up," he writes on his blog. "By simply not giving up, brushing yourself down and trying again, you'll be amazed what you can achieve."
When Rowling feels discouraged, she persists: "The wonderful thing about writing is that there is always a blank page waiting. The terrifying thing about writing is that there is always a blank page waiting," she tweets.
And if you're ever doubting your own talent, Rowling says you may just need a snack.
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Disclosure: NBCUniversal is the parent company of CNBC and Universal Studios, which operates the Harry Potter theme park attractions.