Duplicating the Background Layer

Any time you're tempted to work directly on the Background layer, stop! Instead, Press Command-J (PC: Control-J) to duplicate the Background layer so all your work will be done on a copy. Later on we'll see some specific examples of this technique in action, but for now let's just agree that, in most cases, it's a good idea to duplicate the Background layer. (Yes, there may be some cases where it's not absolutely necessary, but most of the time it's a really good idea.)