Movie producer David Brown is fond of an old joke. It goes something like this:

"Darling," the elderly man says, "if I lost all my money, would you still love me?"

"Of course I would," his young flame replies, "and I'd miss you."

That comes close to summing it up for Brown, who wants to help men hang onto and improve what they've got -- financially and otherwise -- so they won't miss anything. His credentials? Several decades in the trenches, practicing and polishing his own advice. In what seems to be a growing trend, he has distilled these rules into a pint-size book, Brown's Guide to Growing Gray (Delacorte, $12.95).

Foremost among them: Watch out for those indulgences. When Brown was fresh out of college and living in a Manhattan hotel in 1938, he spent more on fine wines and cigars than rent. (His $8-a-week room was so small, he adds, "that when I invited a young lady up, there could be no doubt of my intentions. When you opened the door you fell instantly over the bed.") Somewhat wistfully, he says he had originally intended to come out in favor of liquor. Nevertheless, he now advocates cutting back.

Some other Brownian guidelines:

Don't give in to feelings of old age. "Intimations of mortality were more common for me in my early fifties than my early seventies," says this 71-year-old. "It's as though I passed over the midlife crisis. I don't feel ancient, venerable, or -- God, that terrible word -- elderly. But I don't kid myself that I'm a child. It just doesn't occur to me." His only concession here is to be careful of his references, such as when he mentions "things that others are unlikely to remember, like the Second World War."

As for auld acquaintances, sometimes they should be forgot. "I leave a very good place for faintly boring friends," he says. "I consider myself faintly boring. We sort of tranquilize each other. Some friends, though, are terminally boring, and those you should exorcise. Maybe you can pick them up when you're abandoned by everyone else. That seems selfish, but so be it."

Push broken appliances off the table. "It's frustration," he says. "When nothing else works and no help is in sight, try dropping them. It may destroy them, but you have no other alternative." He claims this works especially well with toasters.

And then there's women. "Maybe I'm oversexed," he speculates, "but it never goes away." "It," in this case, is hormonal interest -- "including the lady I saw across the room last night in the restaurant. I can admire women without ever knowing them at all." What about Brown's third and current wife, Cosmopolitan editor Helen Gurley Brown? "She has me on a long leash."

As half of the motion-picture production team of Zanuck and Brown ("Jaws," "The Sting" and "Cocoon," to name three more conspicuous examples), Brown is not exactly hurting for cash or credit. He admits it may be a little easier for someone in his position to grow gray than for, say, a retired widower making do on Social Security and a small pension. But he points out that he hasn't had a lifetime of bucks in the bank, "and I feel I was able to grow older without difficulty before I had the money."

In fact, he started as an impoverished writer, graduating from Stanford and Columbia. Recently he attended the 50th reunion of both classes, and was appalled to find so many of his classmates using walkers. He could only detect his fellow writers, he says, "by the smell of their vodka and cigarettes." Obviously they haven't been taking Brown's advice. "If I were doing nothing," he notes, "I'd be so tired I couldn't get out of bed."

Oh, yes -- don't take it as a bad sign when you start reading the obituaries before the sports stats. This is completely natural behavior once you start to grow gray. Only recently, Brown says, "when it looked like the Mets might have a shot, did I scan the scores first.