Get More Than Just One Undo?

To get more than just one undo (which you get when you press Command-Z [PC: Ctrl-Z]), press Command-Option-Z (PC: Ctrl-Alt-Z). Each time you press that, it will go back one step at a time until you reach a maximum of 50 steps of undo. What you are actually doing here is stepping back through your history, which keeps track of each step you do as you do it. You can see a list of the steps by going under the Window menu and choosing History. This brings up the History panel, where you can see your last 50 steps (that’s the default. You can increase or decrease this number by going under the Photoshop CC [PC: Edit] menu, under Preferences, choosing Performance, and then changing the number of History States). To jump back to any one of those steps just click on it in the panel.