Her husband died, leaving the woman an estate of $400,000, which she promptly put into a savings account at the bank. Earning interest at a rate of 5 1/2 percent, it brought her about $21,000 annually.

Three years later, when she finally got around to investing the inheritance, she got the shocking news. Had she put the money into an investment keeping pace with inflation, it could have brought her as much as $68,000 each year -- three times what she had been getting.

Washington stockbroker Wayne E. Nelson tells this story as an example of the kinds of costly mistakes people make when they don't take time out to think seriously about their personal financial strategy.

"There are high-powered attorneys out there making incredible salaries," says Nelson, a vice president with Merrill Lynch Pierce Fenner & Smith, "who don't know a thing about managing their money. They get $200 an hour, but never give an hour of their time to their own affairs."

Saturday morning, he suggests, "when you are away from the office and your mind is fresh" is an ideal time to devote to money matters. "Instead, you probably tire yourself out with some mundane house chores. The result: Your house is probably better cared for than your financial future."

As a stockbroker, he obviously believes his profession can be a big help in guiding you toward financial wellbeing. But he also readily acknowledges that to a great many Americans, venturing into the mysterious domain of the brokerage firm can be "intimidating."

"A lot of people are afraid to walk in. They're afraid they are going to walk out with a lot of things they don't understand." One problem, he says, is "the terminology." For most people, "despite their business background or sophistication in their own area of expertise," the language of the stockbroker is "gobbledygook."

To ease the way into the plush offices of his and other stockbroking firms, Nelson has translated language and customs into an easy-to-understand guide, How To Buy Money: Investing Wisely for Maximum Return (McGraw Hill, 163 pages, $10.95). "What we do," he says, "is collect money and put it to work."

Nelson, 36, a stockbroker for 10 years, attributes part of his success to the fact that he grew up in Michigan with "no idea" what a stock or bond was. He was the first Nelson to go to college.

When he got his first investment job here, "I didn't know anything about it," so he felt he had to explain to clients equally unfamiliar with the terminology.

"Once you get in the door," he says, "you'll realize that we're real people. We're not staffed with Harvard MBAs." His own majors were history and English.

Nelson's book is aimed at "successful, fully occupied individuals" -- which means people who have the spare bucks to consider an investment. He also hopes to open "the world of money" to potential investors whose fear of risks have paralyzed them into inaction.

"There is no such thing as a totally safe way to buy money," he concedes. "But there is an important difference between the concept of risk and the emotion called fear. The world of money should be appreciated for the risks involved, but never avoided because of fear."

In the past, a stockbroker's clients tended to be investors in their late 50s, who had educated their kids, bought their homes and had a savings account. More and more, says Nelson, they are seeing "a lot of 20-year-olds" starting out early to build their securities portfolios.

To begin, he says, you should probably have at least $1,000 available to buy, for example, 100 shares of stock. "Most brokers are not interested in large numbers of small clients." Or, you might start with a lesser sum by investing in a mutual fund.

But even before this, he says, you should build up a savings of $5,000 to $10,000 "as a safety net" in case of an emergency. His advice: Put it in a money market fund -- which you can draw from almost as easily as a checking account -- so long as the interest rates remain higher than those at a bank or elsewhere. (If your savings are in securities, you might be forced to sell at a loss if you need money immediately.)

A money market fund, he points out, is also a good way to introduce yourself to a stockbroker, since most handle such accounts without charging a fee. "Go into the manager's office. Say, 'I have $1,000. I want a money market fund.'" A good manager "can match you personally" with a broker.

Another introduction: Set up an Individual Retirement Account with a broker, although in this case there often is a fee. At this point, says Nelson, "You have a relationship. You've started something."

A warning: "Don't go to a friend or relative. It is much more difficult to fire them. You make emotional -- not business -- decisions."

"Once you've got a safety net," he says, "pick an investment that allows you to sleep well. If common stocks just bother you, then you have no business in them. Know who you are, how you lead your life, if you are a risk-taker." And, "Diversify, diversify, diversify."

In dealing with a stockbroker, Nelson advises:

* Pay attention to your portfolio. Don't expect the broker to call, since he or she may be handling hundreds of clients. "The doctor isn't going to call you and ask how you are. But if there is a problem, he'll help you monitor it."

* Ask a broker, "What do you think of...?" when you are considering selling or buying. Don't say outright, "I want to buy." If you give the broker that clue, he or she "may be inclined to agree with you, since it represents a commission."

* Fire a broker who is not making money for you.

* Keep your own eyes open to possible investments. Wide-awake parents who saw the popularity of electronic toys had an opportunity to "jump on the Atari bandwagon. When you spot an idea, that's when you should start investigating if there's still time to make a good investment."

* Rely on your broker as a guide, not as the sole source of information. As a broker, says Nelson, "I will say, 'Here are things that look attractive to me." Remember, "Most analysts are not financially independent."