Glenn Tunstull treats an art exhibition like a fashion show.

Whereas fabrics and patterns decorate a model, swatches and brush strokes dress his canvas.

“Each painting represents where I am today,” Mr. Tunstull said.

An adjunct professor at Parsons The New school for Design in New York city, Mr. Tunstull has held an annual exhibit at the Cousen Rose gallery in Oak Bluffs for more than a dozen years. As a fashion illustrator, watercolorist and oil painter, teaching fashion courses helps keep all three techniques fresh. This summer’s exhibit takes place on Saturday, August 17, beginning at 7 p.m.

“When you are a painter you can live a very isolated kind of existence,” Mr. Tunstull said. “The teaching provides me with an outlet to a young world, and a necessity to stay on top of trends that are ever-changing.”

Lounging, by Glenn Tunstull.

Lounging, by Glenn Tunstull.

For this year’s exhibition, A Summer Day, Mr. Tunstull has focused on incorporating deep, rich colors into the light blue skies and golden sunsets of a Vineyard summer. Two jazz musicians look swanky in a cobalt blue scene while ladies have a cozy conversation on a cottage porch lit by delicate lanterns.

“I have a thing for light,” Mr. Tunstull said, as if admitting a crush.

Surrounded by deep oranges, pinks or blues, the white paint strokes insinuate a rush of light from radiant lanterns, glaring white lawn chairs and the blazing sun.

“Each element has a stroke that is made for it,” Mr. Tunstull said. “A different stroke will represent the glow of a sunset versus the reflection of it in the water versus the surrounding trees or buildings.”

His oil paintings have evolved from abstract impressionism, where extractions of colors represented the story, to more representational depictions of these scenes, where fancy umbrellas, carefree people and wooden docks all play a role.

Mr. Tunstull refers to his technique as “dash-ilism,” a play on pointillism.

“I like breaking up colors to create form and shape in stroke separation,” he said. “But pointillism requires little dots, and I don’t have the patience to paint little dots.”

Mr. Tunstull’s complicated strokes form simple stories. “I just like to capture life and what I see and encounter.”

Mr. Tunstull came by his painting career almost by accident. While traveling with his partner throughout Brazil, Asia and other parts of the world, he would create quick watercolor paintings rather than a photograph to document a moment or particular scene. When he returned home to Brooklyn he decided to have a show for his friends.

“They came and bought all the paintings!” he said. “I expected them to show up and be positive, but they literally bought all the work. And I realized I had a new career.”

East Chop View, by Glen Tunstull.

East Chop View, by Glen Tunstull.

This turned out to be perfect timing as his career as a fashion illustrator was slowing down.

“I needed another outlet, I couldn’t stop being an artist,” Mr. Tunstull said.

After finding the right subject or scene — usually by bike, especially on the Vineyard ­— a painting can take a few months to complete.

“For awhile I just hate them,” Mr. Tunstull said. “They look at me and they fight me and act like enemies.”

In the end he wants his colorful paintings to represent very basic ideas of positivity and beauty. Especially positivity of the modern black community.

“I’m 63, so I come from a long history in America, and part of growing up in that era is you want to show an uplifting image of your people. So I make art reflective of the black community today, and their life on the Vineyard. It’s a very beautiful life that is rarely depicted or seen. There are many people living wonderful existences, and our culture is alive and well.”

The opening for Glenn Tunstull’s exhibit A Summer Day is Saturday, August 17, beginning at 7 p.m. at the Cousen Rose Gallery, 71 Circuit avenue in Oak Bluffs.