As individual investors have begun pouring money into stocks again, they would do well to remember five lessons from the bull market that is now five years old, according to The Wall Street Journal.

1. "Be Skeptical of Experts."

All kinds of supposed experts constantly make predictions about the market. "Take their forecasts with a mound of salt," write Journal reporters Jason Zweig, Joe Light and Liam Pleven.

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"If you act on them, make small moves rather than drastic ones."

2. "Remember What Losing Felt Like."

Before going way out on the risk spectrum now, investors should remember how they felt when stocks plunged in 2008-009, the writers say.

"Memory has done a kind of 180-degree turn for some people," Owen Murray, a partner at Horizon Advisors in Houston, tells the reporters.

3. "Limit Your Risk Taking."

Instead of going all or nothing on stocks, investors would do well to keep a set allocation and stick with it in all market environments, David Allison, vice president at Allison Investment Management, tells The Journal.

4. "Be Wary of Labels."

Trying to figure out how long the bull market will last is difficult, the writers say. "Investors would be better off focusing on whether stocks are valued more highly than in the past.

"Terms like bull market and bear market are eye-catching labels — not forecasts."

5. "Question Performance Figures."

Beware of mutual funds' five-year performance figures, as they don't encompass any bear market periods, the writers say. That's because the bull market began March 9, 2009.

As for stock valuations, the market's price-earnings ratio, based on forward earnings estimates, stands at 15.5, compared with its 20-year average of 16.4, according to The Associated Press.

The stock market is "not cheap, but it’s not expensive either, so I think the market continues to move higher until further notice," John Manley, chief equity strategist at Wells Fargo Fund Management, tells the AP.

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