In case your doggy doesn’t sit when requested to do so by your assistant, go ahead of your pet so you’re facing him and require him to sit yourself. Without delay reward his / her right actions with praise and a treat. The free puppies from time to time need to have a little bit more coaching but…

Practice this a couple times: after your assistant comes through the doorway, you step in the front of your dog as he or she approaches the assistant, face your pet dog and require him to be seated, then offer the reward. After he sits successfully for you 2-3 times, ask your helper to ask your puppy to sit after coming through the door. Some good practice is vital.