Instead of splitting your deferrals across all of the available funds in your plan, think about your approach toward investing: Are you a do-it-yourselfer who will research and monitor your chosen funds? Or do you prefer to be hands off?
"If you don't know what you want to do, then go with the target-date fund," said Aaron Pottichen, president of retirement services at CLS Partners in Austin. "If you do know how you want to invest, then don't go into the target-date fund."
Fees also matter. They average target-date fund had an expense ratio of 73 basis points in 2015, according to Morningstar.
Costs are even lower if you look at target-date funds that are comprised of index funds. Vanguard's lineup, for instance, has an average expense ratio of 13 basis points. A basis point is one-hundredth of 1 percent.
Regardless of how you invest, be sure to check your account at least annually. Make sure that your strategy still works for you and that you're deferring as much as you can, Taylor said.
If you want your 401(k) to reflect your overall financial picture, including assets you hold outside of your plan, you may want to consult with a financial planner. "Everyone needs a plan in place to know how they should be invested for that time in their life," Pottichen said. "As they get older, how does that change?"