Ian,
Try this in order to make a composite:
1. Prepare each football player image, e.g.crop, levels contrast, etc., and save them to a folder on your desktop
2. Do the math and ascertain the size canvas that you will need, then go to File>New>blank file and enter the dimensions
3. Go to File>Place, and serially point to each image in the desktop folder, and place.
4. For orientation, you may way want to open the grid. It will not print. You can drag the images around on the canvas and fine tune the sizes to suit. Each image will be on a separate layer.
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