You've been working for years, perhaps decades, but you were never able to save much of your paycheck. There were kids to feed, homes to furnish, Bloomin' Onions to eat. And the debt -- oh, the debt! Mortgages, credit cards, car loans, student loans -- how can you save for the future when you're still paying for the past?

But then it hits you. Maybe you read an eye-opening article, or ran your numbers through an online retirement calculator, or spoke with a financial advisor -- and it takes hold like a stomach virus: You may have to work for the rest of your life.

It's an awful feeling, isn't it? But don't ignore it. Don't turn on the TV or visit another website to avoid it. Use it, because if you don't save enough, you may not be able to retire. Use that awful feeling to motivate you to get your retirement plan on track -- after all, it may not be too late. Here are five ways to get started.

1. Start saving like mad
OK, this is the obvious one -- but the most fundamental. You must become a habitual, fanatical investor. You'll get some help from Uncle Sam; contributions to employer-sponsored retirement accounts are tax-deductible, and the earnings grow tax-deferred. And your boss might be willing to aid you by matching your contributions. That's some powerful help, but it's only as good as your ability to take advantage of it -- by saving like mad.

Usually, these discussions are accompanied by a chart showing that if you start socking away $500 a month (or some such number), you'll have a tidy sum in a decade or two. And it's true, except for one thing: Someone who can afford to invest $500 a month today can afford to save more in the future, since the average person's income rises through the years.

So, for example, someone who invested $500 a month ($6,000 a year) and earned an average annual return of 8% would have $296,538 in 20 years. However, if we assume that the same investor received a 4% raise each year and increased the amount saved for retirement by a like percentage, that person would have $400,113. So start saving like mad, and increase the amount you save whenever possible -- at least as often as you get a raise.

2. Decide what you want to do for the rest of your life
Despite being the retirement guy here at The Motley Fool, I know that retirement may not be healthy for everyone. For example, one 26-year study of 3,500 former employees of Shell Oil who retired at ages 55, 60, and 65 found that the people who retired at 55 were twice as likely to die during the following decade as those who continued working. We humans weren't built to thrive on full-time loafing.

So maybe instead of aiming for full-time retirement, you should aim for part-time retirement -- complemented with part-time employment in a job you enjoy. There's nothing that says you can't earn money while doing something you like well into your 80s. After all, Alan Greenspan was the chair of the Federal Reserve right up to his 80th birthday, and today Robert Byrd becomes the longest-serving senator in U.S. history at the age of 88. My Rule Your Retirement newsletter has featured interviews with index-investing pioneers John Bogle and Burton Malkiel, who are both in their 70s and have no desire to slow down. They can do this because they're doing something they love.

So think about what you want to do with the rest of your life -- what kind of "work" would you enjoy? Even a modest part-time income can allow you to enjoy a part-time retirement.

3. Consider all your assets
The money you have in your retirement accounts should be considered your No. 1 source of retirement income, but you might have other means at your disposal. We're talking home equity, potential inheritances, and valuables -- anything that could eventually be converted into cold, hard cash.

Financial-planning types debate whether you should make these assets part of your plan, and I understand what they're saying. You always need a place to live, a potential inheritance can be consumed by long-term care or legal squabbles, and collectibles aren't always easily liquidated. But the equity and stuff in your and your forebears' homes does have value, and there are ways (such as reverse mortgages and eBay auctions) to turn them into cash. You'll have to be the judge of how much you can count on such alternative sources. However reliable such sources will be, they're not a replacement for regular, habitual, intelligent investing.

4. Be smart about everything
If you're starting late, you have much less room for error. You have to be at the top of your financial game. This means getting the right financial products -- i.e., mutual funds, insurance, advisory services -- and not overpaying for them. It means taking a look at your budget. It means cutting your taxes. It means getting the right asset allocation.

It means learning as much as possible. Visiting us here at The Motley Fool is certainly a good start. Taking a 30-day free trial of our Rule Your Retirement service -- featuring the latest issue, "8 Steps to Ruling Your Retirement," and the "Perfect Your Portfolio With Asset Allocation" and "8 Steps to Supercharge Your Retirement" special reports -- will get you on the right track. A handful of good books -- anything by the likes of Jane Bryant Quinn, Eric Tyson, Richard Ferri, and William Bernstein -- will also greatly improve your money IQ.

5. Believe you can do it -- with the right plan
If you haven't saved much and think it's too late, meet Lesley Wootton. At age 53, she had just $83 saved for retirement. But in a little more than two years, Lesley went from having a negative net worth to being debt-free and saving $150,000. How did she do it? She improved her job prospects, increased her financial literacy, moved to a smaller home, tracked her spending, and maxed out her retirement accounts, among other things.

It didn't just happen. She took charge, and has a plan to be a millionaire by age 67 -- and she's on track to do it.

It can be done. It's not too late. But you have to confront your retirement reality today, and (for just a while) wallow in that queasy feeling that you may have to work forever. Then, use it as an impetus to enact a smart, aggressive plan. In a matter of time, that queasy feeling will be replaced with the sense of power and control you get when you've changed your future for the better.

Robert Brokamp will retire to a castle in Germany, at least until security finds him hiding in a suit of armor. The Motley Fool is investors writing for investors.