You want to make him comfortable and relaxed so the photo looks natural, not forced. I’ve found the best way to accomplish this is to talk to him during the photo shoot.
Tell him he how adorable he is, or how great his hair looks, or how sexy his beauty mark is. Keep the compliments flowing until you get a shot that reflects his inner poise, confidence and beauty.
And the most important thing to remember is not to make fun of his big nose or hairy ears, because after all, nobody’s perfect.
*Technical info if anyone’s interested: Photo taken in Cow Town near Ronks Road. Sony RX100. ISO 125. Aperture priority f/4.9. 1/1000 sec. Minor adjustments in Photoshop.