Act happy while preparing the meal, like dinnertime is an exciting event. If you have another dog that eats heartily, all the better this will model competitive eating for the fussy dog, and should help him get into the food with more gusto. If the dog still won't eat, don't make a song and dance about it. Any stigma that surrounds eating can affect the dog's relationship to it later on, so try to stay clam and positive.