
This part of the tutorial will include extensive use of layer masks.The mask defines visibility of the parts of the layer: areas where the mask is black are completely invisible, and areas where the mask is white are fully visible. The areas where the mask is gray are semi-transparent. Drawing over the mask allows to reveal or to hide the parts of the layer, and it doesn't destoy the contents of the layer - that's why the masks are so popular!
Important: before continuing, make sure that 'Photocopy' layer is visible.