The document describes how to use layers in Photoshop to combine multiple images. First, the author opened two scanned images side by side in Photoshop. Then, using the magnetic lasso tool with a 4px feather, the author outlined an object in one image to cut it out. This created a marching ants border around the selection. Finally, the author used the move tool to drag the selected object to the second image and the free transform tool to scale, rotate, and position it, combining the images in a single layered file.