It takes a lot of practice to create a believable manipulation cover.
Here are a few examples of covers that I've done. All of these are covers created for users here.
The Beautiful Swindler and the Guns 'N Roses covers are more heavily manipulated covers. They contain multiple elements manipulated together to create a single image. On both covers the images of the man and woman were separate and I put them together over a background image to create the look the customer wanted.
The Earl's Oath cover, on the other hand, is very simple. It's a single image manipulation. The rose PNG was placed on a dark background. I added a drop shadow to the image and set it so it was a good distance to create the shadow beneath the roses. I overlaid a metallic gold image and added a deep purple gradient to the background. And I set the text behind the roses to create depth to the cover. It's a very simple but effective cover design. Just because it's a manip cover doesn't mean it needs several dozen layers. It can still be a manip cover with only a couple of layers.
Let's take a look at putting together a manipulation cover in the next chapter.