Looks like a fun guy! :-) I like his expression and the attitude you captured. Technically, some things that might help here would be the composition. He's kinda just plopped into the middle of the shot, not holding much interest. The flash is a little harsh causing shadows. Looks like it may been taken at night or in a dark room so it may have been your only option. The glare on his glasses is a little distracting. But he looks like he's having a great time. :-)
fun shot, but just a snapshot. the lighting from the flash is really harsh, creating heavy shadows and a bad flare in his sunglasses. The background is cluttered and uninteresting, especially the garbage can.