One of my favorite things to do while photographing is to try and make the person laugh, by being goofy you know. I try to find my clients sense of humor and start making jokes. But let me tell you, it is a task, of that you can be sure. You kinda have to poke the person until they loosen up, and cut loose. You have to pay attention to who they are and find their sense of humor. That's when clients forget all about the camera, and start having fun. Getting to know the person in such a small amount of time is always the goal and will always get you your best results.