The mind is a powerful weapon. How are you using yours?

Warren Buffett, in addition to being the greatest investor of our generation, is also a champion of self-improvement, sharing a trove of advice to help us better our lives.

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

Known as the Buffett formula, he says, "That's how knowledge builds up. Like compound interest." In theory, the Buffett formula should give you an advantage over a lifetime, as it has for Buffett.

And the best way to launch it into daily practice is to do what Buffett does every day: Exercise your mind.

Buffett knows that the mind is the most powerful weapon to succeed in business. To continuously grow yours as Buffett does his, choose to live your life by exercising your mind first! Here are four different ways to do it:

1. Read like crazy

Buffett is a voracious reader to such a level that he has admitted sitting in his office and reading all day. Buffet's famous reading habit is what he attributes as the foundational tool to improve knowledge. He spends 80 percent of his own day reading, and he suggests that anyone hoping to achieve similar success should read 500 pages per day.

Not many of us can carve out the kind of time to heed Buffett's advice to a tee. The point, though, is to make whatever progress you can. Rather than 500 pages per day, most of us can fit in 15 pages, maybe 20 pages each day, improving our level of knowledge in the process. 

2. Create margin to 'just sit and think'

Buffett says, "I insist on a lot of time being spent, almost every day, to just sit and think. That is very uncommon in American business." True. But before you think, "I got too much to do to just sit and think," consider the research of Stanford University psychologist Carol Dweck. She found that success in almost every area of human endeavor can be dramatically influenced by how we think about our talents and abilities.

If you mistakenly believe that your success comes from working insane hours and crossing off an endless to-do list, rather than persevering through habit and hard work, you're operating with what Dweck calls a 'fixed mindset' rather than a 'growth mindset.' 

As counterintuitive as it looks, Buffett operates in a growth mindset by making the time on his calendar to read, learn, and think, which will aid him in making important decisions. For him, this is as natural as riding a bicycle.

3. Invest in your development

"The most important investment you can make is in yourself," Buffett is known for saying.  That includes choosing the right education, training, and professional development to propel you forward in life and business. 

Buffett invested in improving his capacity to communicate better at an early age, which he says will increase your worth. "One easy way to become worth 50 percent more than you are now at least is to hone your communication skills -- both written and verbal," Buffett once said.

He was so terrified of public speaking that he enlisted in a Dale Carnegie course to overcome his fear. "If I hadn't done that," says Buffett, "my whole life would be different.

In his office, you won't see any of his degrees hanging on the wall from the University of Nebraska or Columbia University. But you will see that one award certificate he got from the Dale Carnegie course.

4. Surround yourself with the right people

One summer after graduating from Columbia University, Buffett had to fulfill his obligation to the National Guard and attend training camp for a few weeks. That experience taught him one incredible lesson: hang around people who are better than you.

In Alice Schroeder's The Snowball: Warren Buffett and the Business of Life, Buffett said, "To fit in, all you had to do was be willing to read comic books. About an hour after I got there, I was reading comic books. Everybody else was reading comic books, why shouldn't I? My vocabulary shrank to about four words, and you can guess what they were."

Buffett learned that "it pays to hang around with people better than you are because you will float upward." On the flip side, if you hang around with people that behave worse than you, "pretty soon you'll start sliding down the pole. It just works that way," says Buffett.

The people you choose to be around truly do matter for career progression. When you choose to surround yourself with better and smarter individuals and learn from their success habits, you absorb their knowledge and become better and smarter yourself.

Do the opposite -- spend time with procrastinators, complainers, and pessimists -- and over time you'll become like them, severely limiting your success.

Inc