When a dog is displaying a behavior that I personally don't like, I'll say something like, "No. Baaad." Then I'll stop them from doing whatever it is that I don't like. For instance, I'll take away the shoe that they're chewing on, walk them over to a closet where shoes are, point to the shoes and say, "No. Baaad," then it's back to business as usual.
That being said, I never think that a puppy is behaving badly, I just think that they are being puppies, however, the word "baaad" is something that rolls off of the tongue easily, and dogs learn pretty quickly what "baaad" means when they are in the midst of doing something, it means stop doing that. They usually will stop doing whatever behavior that they're doing at that moment.