Better grab a pencil and pad. Here's exactly what you need to do at each stage from 10 years before retirement to the Big R.

By Liz Pulliam Weston

George Dittenhoefer plans to retire next year. But the 58-year-old public finance consultant still has a lot of questions.

He and his wife, Leslie, eventually plan to move from Long Island, N.Y., to Nevada, but he's not sure when they'll leave. He thinks he knows how much income they'll need, but isn't sure their investments are up to the task. And Leslie, 54, is worried about covering their health-insurance costs in the years before they qualify for Medicare.

"I thought about calling a financial planner," said Dittenhoefer, "but I keep putting it off."

At least the Dittenhoefers have started to plan. Recent research by Fidelity, Putnam and the Employee Benefit Research Institute indicates most workers -- even those within a few years of retirement -- haven't tried to calculate their post-work expenses or created a plan to ensure they'll have enough income.

"Winging it" might have worked OK while you were employed, but ignorance or mistakes in retirement can cost you dearly. Retiring too soon, choosing the wrong investments, withdrawing too much money or failing to plan for health-care costs can all turn your golden years to brass.

We can't promise you'll avoid unpleasant surprises if you plan -- but you can probably reduce the odds. Here's a checklist to get you started. (As you get going, our Retirement Planner can help you make sure the numbers add up.)

10 years out

Think about where you'll live. Demographic surveys show most retirees "age in place," meaning they continue to live in the same house, or at least the same community, as when they retired. But downsizing or moving to a cheaper community can help your retirement assets last longer. Since where you live has a strong impact on your expenses, you'll want to consider your options carefully.

The Dittenhoefers, for example, have equity worth more than $225,000 in their Long Island home. If they sell and move to the Nevada condo they own, they could add that equity to the $350,000 already saved in their retirement kitty. If they stay put for a few years, by contrast, the Dittenhoefers would have to keep paying their mortgage and other home expenses -- a difference of $2,000 or more in their monthly costs.

Imagine what you'll do. Some people don't think about how they'll spend their time in retirement until they wake up jobless. That's a bad idea psychologically as well as financially.

Retirees who fare best are generally the ones who have absorbing interests to pursue, said Ralph Warner, the recently retired author of "Get a Life: You Don't Need a Million to Retire Well" (Nolo Press). Those who wait until retirement often find themselves casting about for something to do, and may discover that the hobby or pastime they thought they would love isn't quite so engaging when they can indulge it full-time. As Warner says, "There's only so much golf you can play."

Speaking of golf, your activities in retirement also influence how much money you'll need. If you want to play the finest courses or travel the world, you'll need to save more than if you like to play canasta and visit relatives.

Boost your retirement contributions. If you're not already taking full advantage of your 401(k), IRA and other retirement options, now's the time to increase your contributions. Use MSN Money's Plan your retirement section to see if you're on track, and try your calculations using different life expectancies. Your chances of making it to age 90 or beyond have never been better; many financial planners now use age 95 as their default life expectancy.

Consider paying down your mortgage. If you still have some cash left over after paying off your other debt and maximizing your retirement contributions, think about getting that mortgage retired before you do. Having the house paid off helps many retirees sleep better at night. Not having a mortgage also means you may have to draw less from your retirement accounts, allowing them to grow tax-deferred longer and reducing your overall tax bill.

Five years out

Cut your risk. You'll still need to have your portfolio tilted toward stocks, but you may want to ratchet back your exposure. Now is also the time, if you haven't done so already, to lighten up on company stocks and stock options. Consult with a CPA or other tax pro before you sell so you understand the tax implications.

Find out what income you can expect. Retirement experts often refer to the "three-legged stool" of post-work income, which is typically made up of Social Security payments, pensions from employers and your own savings:

• Contact current and former employers to see if you have any pensions accrued and, if so, how much you can expect to receive.

• Calculate your income from investments.

The latter can be a bit tricky. The longer your expected retirement, the lower your initial withdrawal rate should be. You might not be able to tap more than 3% to 4% of your investments in your first year without dramatically increasing the risk you'll run out of money. You can use T. Rowe Price's retirement income calculator to see what withdrawal rates are likely to be sustainable. Think about health-care and long-term care expenses. Medical costs are spiraling, and you may not have enough coverage:

• Medicare, the government program that covers most health-care costs for seniors, doesn't kick in until age 65. (Even then, some significant expenses aren't covered, so you'll want to investigate private Medi-Gap polices; you'll find more information from AARP.)

• The number of employers who extend health-care coverage to their retirees is rapidly diminishing, and many of those that do are increasing their former workers' premiums or co-pays. If your employer offers the coverage now, it may not in the future or it may cost more, so have a Plan B. (Fidelity estimates a couple who retires at age 65 with no employer-provided health insurance would need $175,000 to pay for their medical costs in retirement.)

• Medicare doesn't cover most nursing-home expenses, which means you may want to consider buying long-term care insurance.