The clicker is supposed to be a bridge to tell your dog that behavior X is what you want. You need to charge it up first so he knows what the click means (that food is coming). Start by feeding him out of your hand and clicking as he eats. Do this three times. Then hand him a treat and click as he eats it for 6-8 treats. If, however, he is afraid of the clicker, this isn’t going to work. Try clicking it while it’s behind your back or in your pocket to soften the sound. If he’s still fearful of it, try a jar lid. One that has one of those freshness ‘buttons.’ Those make a soft pop/click noise which you can use for now so he associates the noise with treats and correct behaviors. As he gets more comfortable with the idea of the clicker, you may be able to transition to the actual clicker. Not every dog will get used to the clicker however. Our trainer has a dog who runs when she hears the clicker. So she had to be trained using other methods.