The streets of downtown Durham were nearly empty on Thursday morning, the day after Christmas, and I felt sure there would be no people to photograph.

Then this man sauntered down the street, burdened with two bulging backpacks. That’s what caught my eye, the backpacks.

I shot just one picture and moved on. Only after I downloaded the photo did I notice the preponderance of red—in the shoes, scarf, fire hydrant and bows—that carries your eye through the frame.

That’s the beauty of street photography: If you put in the time and the miles, an automatic part of your brain eventually kicks in. As in athletics and artistic performance, practice hones your muscle memory. (Overthinking is how baseball players fall into hitting slumps.) You learn to trust the instinct, the reflex.