If you are teaching go around by luring your dog with a treat, try to focus on your body language while you are doing it, and when you are going further from the object try to keep your body language as similiar to it was when you were closer to the object. When your dog gets it, you can fade out the bigger moves.
Dogs are really great in understanding body language, its a natural way of communication between canines, so it's a lot easier for the dog to understand it, than vocal cues or pointing with fingers.
Sometimes dogs even get too good in reading body language, I have thought my dogs to keep eyecontact and "read" my shoulders while we are doing heelwork. Then I thaught Manda to back-up around me, the cue was a vocal cue and moving my left shoulder slightly backwards. And this was what happened in an obedience test when we were supposed to do "two steps to the left". You can see the result around 20 seconds from start of the video
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http://www.youtube.com/watch?v=q-TZcl3IpYE