Pretty much all the brad templates on this site follow the same make up. There is a background layer, an "edge" layer (often metal) and then the plastic layer. When using the brad yourself, you can alter any layer, but mostly you'll want to work with the background layer.
You can lock the layer and use the paint bucket to change the color.
You can clip on a paper.
You can add an element.
What else do you do to your brad templates?