Each year, Forbes releases its list of the 400 richest Americans. This was particularly notable in 2007 because you had to have at least a $1.3 billion to be included.

As you might expect, a significant number of the folks on the list made their fortunes by investing. That subset includes Warren Buffett (worth $52 billion), Carl Icahn (worth $14.5 billion), and Jim Simons (worth $5.5 billion).

So here's important lesson No. 1: You can make a lot of money if you learn to manage your portfolio like a pro.

Easier said than done ...
Of course, that collection of billionaire investors offers no clue regarding what strategy is most likely to make you a billionaire. Buffett is a dyed-in-the-wool value investor. That strategy has helped him grow book value at more than 20% annually at Berkshire Hathaway for more than 40 years, on the back of investments in boring companies with competitive advantages at value prices such as Geico and Washington Post. That investment tack continues in the company's portfolio today, with UnitedHealth (NYSE: UNH) among its current holdings.

Simons, though, can point to 34% annualized returns at his Renaissance Technologies' Medallion fund since 1982, net of what are believed to be some incredibly stiff fees. He favors a mechanical strategy, based on computer models that are constantly refined by an army of Ph.D.s. The firm's most recent 13-F filing revealed more than 3,200 positions, including Bank of America (NYSE: BAC), Bankrate (Nasdaq: RATE), and Barnes & Noble (NYSE: BKS).

So while there is no best strategy, important lesson No. 2 is obvious: You gotta dance with the one that brung ya.

Say what?
Colloquialisms aside, all of these investors are astoundingly successful because they've figured out how they make money best, stuck with their strategy in good times and bad, and refined their best practices over time.

Buffett was mocked during the technology bubble, when companies that he avoided, and professed to understand more poorly than others, were zooming to the moon. But they've come back to earth, and Buffett's still doing just fine today.

Icahn has a reputation as a corporate raider; he's made a lot of money instituting changes at underperforming companies. Although Icahn's recent efforts at Time Warner weren't as successful as past efforts, he earned a windfall when Oracle (Nasdaq: ORCL) announced that it would buy out BEA Systems (Nasdaq: BEAS).

And Simons doesn't try to analyze businesses as Buffett does, because that's not where his expertise lies.

Mimic the masters
The secret to successful investing, then, is not found in any single strategy, but rather in picking the strategy that's right for you and executing it faithfully. As lauded NYU finance professor Aswath Damodaran writes in his book Investment Fables, "Each strategy has the potential for success if it matches your risk preferences and time horizon and if you are careful about how you use it."

That's it. That's the secret. Because if you get too cute -- chasing hot sectors, buying high and selling low, and giving yourself only six months or less to master a given investment strategy -- you're simply setting yourself up for failure.

Allow myself to introduce ... myself
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This article was originally published on Sept. 30, 2006, as "Join the Billionaire Boys Club." It has been updated.

Tim Hanson owns shares of Berkshire Hathaway, as does The Motley Fool. Berkshire Hathaway and UnitedHealth are Inside Value choices. Time Warner, Berkshire Hathaway, and UnitedHealth are Stock Advisor choices. Bank of America is an Income Investor pick. Bankrate is a Rule Breakers selection. The Fool's disclosure policy assures you that no stocks were harmed in the writing of this article.