Shooting a 35mm Nikon with telephoto lens doesn't make you a photographer. Cycling through India, Nepal and Pakistan doesn't make you a travel writer. And wearing an ultra-mini on your killer bod doesn't make you a fashion model.

Practice does. Practice, plus talent, a little luck and maybe some connections. Mike Handley calls it "paying your dues." A professional model and announcer, Handley, of Centreville, Va., has been paying long enough to be earning more than $100,000 a year with his rugged face and believable voice.

With the population aging, many better-than-average-looking grown-ups, verging on gray, ask Handley how they can start doing commercials for telephones and televisions. He burns.

"Where's their experience?" he fairly shouts. "Have they paid their dues?"

When Handley was 3, he was watching "The Milton Berle Show" on television and was attracted to a scene featuring the show's background and props. He promptly built a stage set in his bedroom. To sleep, he had to dismantle it.

At 13, he begged a job as a cue-card holder in a local television station. After working his way up in production, he eventually emerged from behind the camera. Ten years ago Handley set up shop as a free-lance model and voice. He landed only four short jobs in the first seven months. That's what he calls paying dues.

"That's why most people don't make it," says Handley, 39. "Most people don't have the luxury or the guts to last seven months. Usually they last three weeks and then give up."

Mary Beth McAndrews-Noll, an independent video producer, agrees. "Agencies get phone calls constantly, and people arrive on their doorsteps wanting to be models. It's sort of considered a glamorous life style, but people don't realize how difficult it can be, how few people earn a decent living at it."

The demand for models is weighted heavily toward men, she says, especially for corporate and industrial settings. When women appear in business ads, they are typically "the girl behind the computer."

There are rare occasions, however, when open auditions are held, such as the recent one in Washington for bigger women. Last month, more than 300 women -- dress size 14-24 -- responded to a Woodward & Lothrop ad that announced a search for "fuller figure beauties." According to a Woodies spokesman, 30 women, including a handful with professional runway experience, were selected to model for an Oct. 24 fashion show. One lucky woman will go to New York on a fashion shoot and appear in the Woodies spring catalogue.

Meanwhile, the market for senior models is glutted with former teen-age runway mannequins who have maintained their skills and shape, says McAndrews, a former marketing director of a modeling and talent agency. Since there are more bodies than opportunities in this category, the chances of an older (that is, over-21) model beginning a career are slimmer than Twiggy.

Barbara Summers, 43, of Teaneck, N.J., is philosophical about the waning requests for her still-lovely face and figure. In the last five years she has posed for mail-order catalogues, department store newspaper ads, cosmetics, AT&T telephones and IBM computers, to name a few.

"When you're in your forties," says Summers, "it's a surprise that you're still attractive, although when you're in your twenties, you're supposed to be attractive. I guess people think it's shocking that 40-year-olds are capable of wearing the modern, stylish clothes that designers are actually designing.

"All models call themselves 'girls' no matter what age they are," says Summers, a 17-year veteran who causes heads to turn on Manhattan streets. The problem, she says, is that as age brings fewer jobs, it also brings greater intelligence. "When you're earning only $20,000 a year modeling, you're too smart to be willing to stand in one spot and wear ugly clothes and do what people tell you to do."

Many talent agencies "would love to get their hands on a pretty face that can talk," says McAndrews, who is in the Philadelphia suburb of Haddonfield, N.J. It's not that models are dumb, she says, but they have not had training -- diction classes, private teachers.

"You have to be attractive and have a great smile, but you also need training in diction. The slightest little vowel that becomes a colloquial pattern is going to throw you off. You can't sound like New York or the Midwest, because people have to see you in their world."

Responsible agencies turn away most of the dabblers and dilettantes, says McAndrews. "We're looking for serious professionals, people who keep up with their craft. They have their photos consistently up-to-date, their re'sume's are current, they keep reels of half-inch or three-fourths-inch videos on themselves."

Handley is a perfect example. Although he is not gorgeous, he is a pro, so he gets modeling assignments. His four-minute video, available on Beta or VHS format, shows more than three dozen clips of him selling used Cadillacs, groceries, a humane society and President Reagan. He has an audio tape, too, and a scrapbook of articles by and about him in trade publications.

Handley invests part of his six-figure income in his business. One recent month he spent $4,500 on advertising in trade journals. He makes countless long-distance calls setting up future engagements. He solicits testimonials from satisfied customers and uses no fewer than 48 agents around the country.

Says McAndrews, "We need professional people who can be available at all times, who answer calls immediately, because advertisers are always working on a very tight time frame. Usually they want to see someone or book someone in half a day after they call us."

McAndrews spends so much time talking about attitude, she almost discards the physical appearance as inconsequential. Almost, but not quite. The "perfect size" male is 6 feet tall and wears 40-Regular clothing off the rack. Although he has a perfect physique, he's not "madly attractive." (Handley, for instance, is four inches too tall; he rarely models clothing.) The "perfect size" woman is 5 feet 8 inches, and wears clothing sizes 6 to 8.

Most agencies, says McAndrews, also book "character types" who can parade as blue-collar workers or doctor-types, "people you wouldn't look twice at on the street." She has one model, she notes, who "can put on a hard hat and look as real as a construction worker. He can put on a tuxedo and look real. He can put on a white doctor's coat and look professional. He's a good-looking, everyday man who can cover the territory."

McAndrews meets many hopefuls who don't make the grade: adult women who have free time and want extra cash. They think it would be fun to play glamor-lady for a day, with cameras, directors and makeup. She usually tells them that modeling is a job, like any other, and it takes years of work to do it well.

The rewards of professional modeling are emotional as well as financial, says Handley. "I'm having a ball doing what I love. I get up every morning and thank God that I can set my own schedule. I don't have to worry about showing up at work and having someone fire me."

Susan Perloff is a slim Philadelphia writer.