I've been practising my photo compositing skills recently - my first challenge was to create a fictional Book Cover Design from scratch. I used free design elements from deviantart.com to speed up the process. the soldier was placed on to the background and recoloured to suit the colour balance of the background so it appeared a natural fit. Then I added lighting effects to make him stand out a bit more and look more dynamic - as well as a flare on his gun barrel. I also then added the man at the back of the image to add some tension to the scene. Text etc was added as a final touch.