After graduating from college, Grant of Millennial Money moved back home with just $2.26 in his bank account.

"That was a huge wake-up call for me," the now 31-year-old — who goes by his first name exclusively — told CNBC. He took a screenshot of his balance, set the goal of having $1 million in assets in five years, and immediately started educating himself.

"As soon as I began this journey, I looked up the best reviewed personal finance books on Amazon," says Grant, who reached seven-figures exactly five years after taking the screenshot, thanks to a side hustle that he turned into a lucrative consulting company.

Since, the Chicago-based self-made millionaire has read over 360 personal finance books and "the best book on money period" happens to be the first one he picked up: "Your Money or Your Life," by Vicki Robin and Joe Dominguez.