Warren Buffett has accumulated millions of followers who've learned that Buffett's formula for success comes from making smart investment decisions. But investing, in and of itself, may not strictly involve where to put your money. 

Years ago, Buffett shared with Good Morning America something different to achieve success:

 Investing in yourself is the best thing you can do. Anything that improves your own talents.

You may be wondering, what's a good starting point to "invest in yourself"? Besides getting more education or training in a particular trade or skill, the overarching principle behind Buffett's tip is to never stop acquiring knowledge -- the kind of knowledge that betters yourself as a whole person, not just as a financial investor.

The strategy for investing in yourself 

One of those famous Warren Buffett tips -- what he calls the key to his success -- is a strategy that he follows religiously: Go to bed a little smarter each day.

That's where the Oracle of Omaha separates himself from the pack. He has literally applied this over his lifetime to gain an enormous competitive advantage.  

The way he does it is to simply grow his mind -- something that anybody with a fair amount of steady discipline is capable of doing. Buffett knows that the mind is the most powerful weapon to succeed in business, which is why he spends 80 percent of his working day reading and thinking. When asked how to get smarter, Buffett once held up stacks of paper and said he "read 500 pages like this every day. That's how knowledge builds up, like compound interest."

Buffett also is a big believer in investing in improving your communication skills. In a video posted on LinkedIn, Buffett said,

If you can't communicate, it's like winking at a girl in the dark--nothing happens. You can have all the brainpower in the world, but you have to be able to transmit it. And the transmission is communication.

Buffett has stated that investing in developing your communication skills can "improve your value by 50 percent." 

Finally, you'll want to invest in improving your business relationships. Buffett has always advised that success relies on surrounding yourself with the right people. Buffett spoke with some college students a few years back and said, "You will move in the direction of the people that you associate with. So it's important to associate with people that are better than yourself."

As the famous saying goes, we are the average of the five people we spend the most time with. Make sure to associate with those further along the path who can potentially help you learn new things, grow, and advance your career. 

Buffett's lifelong pursuit of learning and investing in himself, which he shares with his longtime Berkshire Hathaway partner and colleague Charlie Munger, is the secret sauce of his success.