Investing isn't a simple endeavor, especially as most Americans, understandably, don't have a deep knowledge of financial markets.

Losses suffered during the 2008-09 financial crisis have made investors gun-shy.

Editor’s Note: Retire 10 Years Earlier With These 4 Stocks

CNNMoney lists four common mistakes you should avoid in the process.

Failing to invest in stocks. They offer the best long-term returns of standard assets, yet many Americans are afraid of them after their 2008-09 plunge. "This is the least beloved bull market of my career," Robert Doll, chief equity strategist at Nuveen Asset Management, told CNNMoney.

Investing in riskier assets. With interest rates low, many investors are venturing out on the risk curve for assets such as high-yield bonds. "Investors are so interested in getting the additional yield that they're forgetting how much additional risk they're taking," Kate Warne, investment strategist for Edward Jones, told CNNMoney.

Short-term thinking. Investors often purchase assets based on past returns rather than future potential. "Rear-view mirror investing is the greatest pitfall," Jeffrey Rosenberg, a fixed-income strategist at BlackRock, told CNNMoney.

Forgetting inflation. At some point inflation will rise and bonds will suffer. Many investors aren't ready for that.

A recent Wall Street Journal story listed five unconventional investments you should avoid: liquid-alternative funds; leveraged ETFs; non-traded REITs; structured notes; and unconstrained bond funds.

Editor’s Note: Retire 10 Years Earlier With These 4 Stocks

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