'If you're not investing in yourself, who is?' says self-made millionaire: Here are 2 smart ways to start

"I'm willing to invest in myself. I've always made a return on that investment," says Tiffany Haddish.

Investor and author Grant Sabatier says building a relationship with your money is the key to having more of it.
Source: Grant Sabatier

Actress and comedian Tiffany Haddish is a New York Times bestselling author and a Grammy and Emmy award winner, who has amassed an estimated net worth of $6 million. Despite her success, Haddish is still spending money to advance her career.

"There's this big film festival coming up and I'm seeing what they're doing for my counterparts: A lot of them are getting paid to be there. I am not. I am paying to be there. But I'm willing to invest in myself. I've always made a return on that investment," Haddish recently told The New York Times Magazine.

Tiffany Haddish arrives for the 2019 NBA Awards at Barker Hangar on June 24, 2019 in Santa Monica, California.
Lisa O'Connor | AFP | Getty Images

Regardless of how successful you are or the wealth you've accumulated, it's smart to keep investing in yourself, says self-made millionaire and FIRE adherent Grant Sabatier: "If you're not investing in yourself, who is?"

Shaan Patel, the CEO and founder of Prep Expert SAT & ACT Courses — who is also a self-made millionaire and won an investment on ABC's "Shark Tank" in 2016 — agrees: "As my business partner Mark Cuban has said many times: 'The best investment I ever made was investing in myself, first and foremost.' Unfortunately, most people do not take this advice seriously enough."

Here are two smart, straightforward ways to start investing in yourself, according to Patel and Sabatier.

1. Take people you admire out to lunch

At the beginning of his career, Sabatier, who is also the author of "Financial Freedom" and the founder of websites Millennial Money and, invested in taking people out to lunch. "I'd spend $50 on a lunch with someone more senior in my company just to show them that respect and show that I value their time and use that as a learning opportunity," he says.

That $50, he adds, "ended up paying off significantly over time for me."

How a FIRE supersaver plans to retire at 32

Video by Courtney Stith

One of the first projects Sabatier landed, building a website for a realtor, was a result of one of these lunches. "It was a huge step in my career because it allowed me to take skills that I was developing on the side and turn it into a side hustle, which eventually became my own company," he says. "And most of the clients that I got building that website were from referrals."

Oftentimes, millennials network with peers. But Sabatier says connecting with more established people in your field is often more rewarding for you and for them. "They have 20 to 30 years of experience doing something that you want to do, and you're gonna learn so much more from them in just an hour lunch, and oftentimes they're gonna want to keep helping you."

2. Spend money on books

"Investments in yourself don't have to be large. One of the easiest investments you can make to improve yourself is to buy books," says Patel.

"Every month, I make sure to buy one book related to investing, business, or self-improvement. By reading one book a month related to these topics, I generate new ideas that have produced significant returns both in my personal finances and business revenue," Patel says.

Educating himself is the reason he's had so much success, Sabatier says: "I've never taken a finance class in my entire life and now I teach people all over the world how to manage their money, and everything I've learned is from books and YouTube videos."

More from Grow: