How do people with working dogs show affection for their dogs?

I do not own working dogs, but I do believe that handlers treat jobs as a big game. Of course, it has to be something a dog likes to do it so often! Working dogs and their handlers have a relationship based on understanding and respect. For some, it is hard to truly express love for every single dog, but I saw a show once of a man that owned more than forty working sled dogs and he knew each one by bark and sight. Every single dog. Amazing.