Before you dive into the market for the new year, professionals advise one key resolution: don't get cocky.
"Don't be greedy. You see 30 percent gains and everyone feels like, 'Wow, I'm a great investor. Look at all the money I made this year,'" said Joe Magyer, senior analyst at The Motley Fool in Australia.
"In reality, the individual investor could have bought just about anything and they would have killed it this year," he said.
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By any measure, U.S. stocks have had a stellar year, with the S&P 500 index surging nearly 30 percent, its biggest jump since 1997, outpacing the gains of the go-go dotcom boom years. The Dow Jones Industrial Average tacked on 26.5 percent in 2013, while the tech-centric Nasdaq totted up gains of 38 percent.
"If you are feeling that compulsion, like 'man, I really know what I'm doing.' That's probably the time to hit the brakes and just relax," Magyer told CNBC.