If you messed up big time, or you don’t want to proceed any further, and want to go back to the design as it was last saved, then we’ve got two ways to do that. The more obvious way is to exit out of the Design Center (click X near the top right hand corner) without saving, and reopening the design. Or you can click the More tab then click the Start Over button.
To completely clear your design/canvas, click on Clear Canvas instead. This button will remove all items appearing on the currently selected side of your design (front or back side). This is only if you truly intend to ground zero your design.