As a teenager, I was very shy and it was difficult for me to make eye contact with strangers, let alone speak to them. As I moved into my twenties and entered the corporate workplace this attitude had to disappear, especially when every job I had seemed to involve sales of one kind or another. My fear of strangers is long gone and that has come in handy when I am out photographing reference material.
Last year a boy was fishing on the dock while I was out painting one evening. He was pleased and somewhat flattered when I asked him to pose with his fishing pole in hand. When you take the time to explain why you want to take a picture and that the subject just might end up in a painting, most people are eager to help. I kept this painting generic enough that a viewer can't really tell who the model is, unless perhaps the viewer is his mother. :)
Last weekend I took hundreds of invaluable reference photos. I used my charm, my wit and this well-rehearsed question: "Would you mind posing for a photograph? I'm an artist and I would love to put you into one of my paintings?" I was at a fitness exposition, surrounded by thousands of interesting individuals and my utter lack of shyness allowed me to take dozens of reference photographs.