If you have to put your dog to sleep for any reason, perhaps because he's too sick or too old, talk to him. Tell him what's going on. Tell him the doctor thinks it's better for him and that it's time to go. Hug him and be with him all the way through it. Don't just throw him in the clinic and let them do it or anything like that. He understands that he has to go, but he needs love to be able to go. He doesn't mind going, but he needs you to tell him that you still love him; it's just that he has to go. And then bury him; be nice to him.