Midway into “Big Sonia,” Sonia Warshawski, the outsize centerpiece of this poignant documentary, ushers viewers into her bedroom, lifts a pillow from the bed and extracts from its satin case a small plastic bag.

Inside is a coral scarf — a “shalek,” as the Polish-born Ms. Warshawski calls it — limp and riddled with moth holes. Yet to Ms. Warshawski, its beauty is somehow intact.

“You can see the color,” she said during a visit to New York last week. “It is so vivid.”

Over the years, Ms. Warshawski, who arrived for an interview at The New York Times wrapped in her signature faux leopard coat, has cultivated an eye for things colorful and vividly expressive. It is a gift she nurtured at John’s Tailoring, her basement shop in a now-defunct mall in Kansas City, Kan., where, for almost four decades, she nipped waistlines, tweaked seams and adjusted hems for her devoted clientele.

Like the scarf, it is a gift she inherited from her mother, a woman with an acute sense of style, who wore that little shawl to bring out the colors of a favorite blazer, flecked with orange, beige and brown. “She would have been a designer,” Ms. Warshawski said, “if she had made it.”