Once you've given up the notion that you can pick the next hot mutual fund, you can focus on the real key to investing for retirement. And that's creating a blend of stocks and bonds aggressive enough to generate the returns you need but not so risky that your retirement savings will be decimated by market meltdowns.
When you're younger and have more time to recover from short-term setbacks, you can afford to tilt your mix toward stocks. As you age and become more vulnerable to losses, gradually shift toward bonds. It's pretty simple.
If you don't have the time or inclination to do this yourself, go with an increasingly popular option known as a target-date retirement fund. You simply choose a fund with a date that roughly corresponds to the year you plan to retire - say, the 2035 fund if you're in your early forties - and you get a fully diversified portfolio suitable for someone your age. Many large fund firms, including Fidelity, T. Rowe Price and Vanguard, offer these options, while 85% of 401(k)s at large companies offer or plan to offer similar funds.