I'm using Photoshop Elements 4 for this tutorial, but the required features are available in other versions of Photoshop and Elements, as well as other photo editors, like Paint Shop Pro. If you need help adapting a step, feel free to ask for help in the discussion forum.
Right click and save this practice image to your computer: dreamy-start.jpg
To follow along, open the practice image in the standard edit mode of Photoshop Elements, or whatever photo editor you'll be working with. You may follow along with your own image, but you'll need to adjust some of the values when working with a different image.