You can create a collage or montage in Adobe Photoshop or Photoshop Elements in several ways, but the following method is the simplest. Following the steps below, you add each new image to the collage image as a separate layer. This process allows you to manipulate each image individually. When all of your images are assembled in the final image, you can resize or move the layers (the added images).
If the Layers palette does not appear, choose Window > Layers. See Photoshop or Photoshop Elements Help for more information about using Layers and the Layer palette.