Billionaires make a lot of money, so it's understandable that the investing public likes to follow what they do in their financial lives. Now, it goes without saying that some uses of billionaires' wealth, such as acquiring a company or buying a private jet, are out of reach for most of us. Even so, there are a few good lessons to be learned from this exclusive group and how they put their cash to work.

We asked three of our writers to discuss some of the habits of billionaires and what you can learn from them. Here is what they had to say.

Man wearing suit holding out many $100 bills

Image source: Getty Images.

Jason Hall: One only has to look through a list of the world's richest people to see what the vast majority of billionaires do with most of their money. That is, they leave it invested in the thing that made them wealthy.

Most of the world's billionaires either made their fortunes in the business world or inherited it from a spouse or parent who did. For most of them, like Carlos Slim Helu (Mexican telecom), Warren Buffett (Berkshire Hathaway), Charles and David Koch (Koch Industries), and the heirs of Sam Walton (Wal-Mart), the majority of their wealth remains in the companies they built or inherited.

There is a lesson regular folks can learn from this: Let your best investments run.

It may be tempting to sell your stocks when you have a nice gain, but you'll never get life-changing returns that way. Unless you're willing to stay invested in great companies for decades -- and let the power of compounding returns pay off -- you're going to spend a lot of time chasing the market and getting sub-par returns.

Learn a lesson from a billionaire or two: Hold on tight to your biggest winners. 

Dan Caplinger: It's easy to think of billionaire investors as selfish hoarders of financial resources, but a surprisingly large number of billionaires use their wealth toward the greater good through their charitable endeavors. In particular, Warren Buffett and Bill Gates have been instrumental in encouraging other billionaires to support charitable causes, with their efforts leading to what has become known as the Giving Pledge.

The pledge involves billionaires committing to giving at least half of their wealth to charity, either during their lifetimes or at their death, and more than 100 billionaires have joined Buffett and Gates in giving their word to abide by the pledge.

Causes supported by the pledge vary widely. Buffett is a huge supporter of the Gates Foundation, which has a wide-ranging mission to help people throughout the world live healthy and productive lives. Mark Zuckerberg has made numerous gifts to school systems in the U.S., while former mayor Mike Bloomberg has had a history of donations to environmental, public health, educational, and artistic endeavors.

Cynics will point out that billionaires get some lucrative tax benefits from making charitable contributions, including avoidance of capital-gains tax on gifted stock and deductions, in many cases, for their donations. Nevertheless, their philanthropic endeavors represent money out of their pockets, and they have made meaningful differences in the lives of millions across the globe.

Matt Frankel: One thing that many (but not all) billionaires have in common is a willingness to take calculated risks.

Perhaps the most famous cases are billionaires who left ivy-league colleges in order to pursue their dreams, like Bill Gates and Marc Zuckerberg did -- both thought they had game-changing ideas and decided the risk justified the reward potential. However, an entrepreneurial and risk-taking personality is a common trait among billionaires.

Still, it's important to note the difference between taking a calculated risk and being reckless with your money. Buying a bunch of out-of-the money call options on Apple because you feel the iWatch is going to be huge is reckless. On the other hand, if you thoroughly analyze the reward potential of the situation, and it makes sense in terms of the risk you take, buying a large amount of Apple stock might be a good idea in that situation.

For example, Bill Ackman has said Fannie Mae and Freddie Mac common stock is the most interesting investment in the markets from a risk-reward standpoint, and he and his Pershing Square hedge fund have actually become the largest shareholder of both agencies' common stock. Yet, his investment in Fannie and Freddie is fairly small relative to the overall size of his portfolio -- about $500 million out of Pershing's estimated $18 billion in assets.

It's an extremely risky investment, but it's also one whose size and reward potential makes sense to those involved. It's an amount of money that Ackman and his clients could reasonably afford to lose if things don't go their way, and could easily be a ten-bagger if it's successful.

Now, I'm not saying you should or shouldn't invest in Fannie and Freddie, but the point is that if you want to invest like a billionaire, you can't be afraid to take some risks. Just make sure the size of your risks are responsible, and that you take these risks with money you can afford to lose if things don't go your way.