Basically the dogs take a track and eventually they will push the deer by one hunter or another. Several hunters set up around the area the dogs are working. You listen for the baying dogs and as they approach you keep your eyes open looking for the deer. dogs further back equals a slower moving deer so many guys want a dog pack that isn't super fast runners.
Training the dog to take deer tracks and ignore all other animals is done thru a process we call "trash breaking" and many use the same shocker training system that upland bird hunters use.