5. Not getting the full employee match on your 401(k). If your company offers to match a portion of your 401(k) contribution, take advantage of it. "It's free money," Blackwelder says. "Never leave free money on the table." A third of employers match up to 3 percent of employee salaries, according to a 2011 survey by trade publication PlanSponsor.com.
6. Not taking advantage of all retirement options. If you're maxing out your 401(k) contributions, think about funding a Roth IRA, Weston suggests. A Roth IRA is an individual retirement account that enables you to set aside money after taxes. It allows for tax-free growth of your money in lieu of getting a tax deduction, and can consist of an array of investments: stocks, bonds, mutual funds, certificates of deposits, and money market accounts.
If you have both a Roth IRA and a 401(k), you'll have two pots of money to draw from for retirement—one that's taxable and one that isn't. "It will give you more flexibility," Weston says.
7. Making knee-jerk reactions to the market. Many people make the mistake of trying to time the market, often jumping out of investments at the first sign of trouble. "The system really works if you keep your money in and try not to panic," Weston says. If you pull your money out every time the market swoons, you'll likely be selling at the bottom and buying back in at the top, which will take a toll on your portfolio, Weston says.
8. Putting children's college funds ahead of retirement. Don't put away too much money for your children's college fund if it's at the expense of your retirement fund. "Retirement should take the priority over saving for college because your children can borrow for college, but if you've saved so little for retirement, you can't go to a bank and say that you need money for groceries and medicine," says Gail MarksJarvis, author of Saving for Retirement (Without Living Like a Pauper or Winning the Lottery). With most people, the thought process should be reversed: Retirement savings should come before college savings.
9. Not preparing for long-term care. The costs of medical care in the late stages of retirement can be so large that even a good long-term care insurance policy may not cover the costs, MarksJarvis says. Often, consumers buy long-term care insurance that covers about $150 a day in care, she says, but the average annual cost for a private room at a nursing home in 2012 was $81,030, according to research firm Genworth. That leaves more than $26,000 uncovered by long-term care insurance. "These are the things that people don't want to think about, because the realities can be overwhelming, but they have to think about them," MarksJarvis says. As such, many people will need additional funds to cover the cost of long-term care.
10. Not developing a distribution strategy. Covering retirement costs involves more than simply pulling money out of various forms of savings. Blackwelder strongly recommends developing a distribution strategy, to determine the best way to tap your funds. "It's arguably as important as having an accumulation strategy," she says. "If you've got no idea how to turn what you've saved into an income stream for the rest of your life, you're not setting yourself up for a successful retirement."