You may want to check this video by George Peirson.
If you haven't tried out Blend Modes in Photoshop Elements then you are missing one of the best tricks around. Let's see what Blend Modes are and how you can use them. Then I will do a couple of quick projects utilizing Blend Modes, one is a fast way to make interesting background images, and the other is a great way to add more interest to a boring sky.