Shadow of man wearing cowboy hat against orange adobe wall, San Miguel de Allende, Guanajuato, Mexico.
The technique is simple. Find a wall you like in good light and get your camera ready and prefocused on your “spot”. Then wait patiently until something interesting comes along. Click. Repeat.
Sometimes I will simply leave my camera on the tripod at a low height across the street from my “spot”, then trigger the camera with a cable release while standing and looking away. People don’t even know you are taking their photo and react more naturally.
Canon 1Ds Mark II. 90mm. ISO 100. 1/13 second @ f/14.