"I think hair stylists are more psychologists than we are technicians," said Melinda Smith, mixing up a bowl of noxious-smelling goop and checking the tension of the rollers in a model's hair. "I can do more for someone than a psychologist can because I can touch them."

Smith was one of 2,000 professional hair stylists, barbers and students who came to the new Convention Center yesterday for "Looking Good '83," an all-day hair-cutting and styling competition and fashion show sponsored by United Food and Commercial Workers Local 400 to benefit Children's Hospital. Winners of the local coif-off--Bill Wilfong, Linda Vito, Jane Brokenik and Tim Gray--go on to represent Washington next month in the national competition in St. Louis.

Smith, from Columbus, Ohio, has been working with hair for 16 years. "How many heads is that? Let's see, 2 1/2 days a week, 50 heads a day, 16 years, you figure it out."

"Ninety percent of the job is talking to your client," said Smith, while demonstrating new hair styles on several volunteer models. "You have to understand what they're going through. For instance, if a woman is going through a divorce, she's feeling frumpy about herself, like no one notices her. That woman may want a highlight or a totally new design. Another woman may not want to be noticed."

The acrid scent of ammonia and hair spray filled the cavernous, drafty Convention Center, as did the sounds of disco music, clicking shears, spray cans and blow dryers. The hall was a beautician's bazaar, lined with booths purveying a variety of exotic potions that would make an alchemist envious. Tables were heaped with relaxers, texturizers, conditioners and rebuilders in colors not found in nature, and menacing-looking appliances bristling with metal spikes and sharp edges.

"I never touched a head before last February," said student cosmetologist Gary Elliott, 27, who worked his model Trina's hair into a spiky cut he described as "the trend: volume on top, short on the sides, layered to length.

"I'm basically artistic, which makes it easy to follow the lines on the head," Elliott said. "You can be artistic and make money. If I wasn't cutting hair, I could be off somewhere painting pictures for nothing." Behind him, while models waited like docile poodles for the judges of the "men's freestyle competition," business-suited male models strutted on stage, swinging umbrellas overhead to the Weather Girls' disco hit "It's Raining Men."

"Of course, I wouldn't want to limit myself just to hair," said Betty Rodriguez, a student at Lor France cosmetology school in Lanham and first-place winner in the student cosmetology competition. "I'd like to go to makeup school after I finish cosmetology school. I want to work in a place where you could, like, totally make somebody over." Rodriguez gave model Jamie Pyle a "bi-level cut," and said the two coordinated their electric purple outfits. "I didn't want to go up there and have our colors, you know, totally clash." Pyle, in a purple-checked blouse and tight black pants, was posed dramatically for the judges, head thrown back, clutching a fan. "I told her to pose like that, you know, with the fan and the snotty look," Rodriguez said.

Most of the stylists appeared to have put as much work into their own looks as into their models' hair. Veronica Nelson, a student cosmetologist from Oxon Hill, wore a dramatic black chiffon flounced dress with her hair pulled back in a short braid. "I know money is tight these days," said Nelson. "But I think it's very important how you look. If a woman wants to be beautiful, she's got to pay the price."