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How to teach a dog to smile
Pay attention to time.
Teaching a dog to smile is similar to teaching him any habit, so you'll need to know the basic tenets of dog training. Timing makes a huge difference when it comes to successfully training a dog.
A dog must be rewarded the instant he obeys a command. Many people reward their dogs with a small treat or positive verbal praise, such as " yes! " or " good job! " some people invest in a clicker, a small mechanical device that makes a clicking noise when a button is pushed.