When you fire up the program, you will notice the layers panel right away as it the largest option box. Here, we have a screen shot of what the layers will look like.
As you can see, you can group the layers up, create clipping masks, a layer mask, and layer effects. All these are tools to help benefit you as you edit your work in a quick and easy fashion that doesn’t destroy your work.
On top of that, there are extra color options that could benefit your need to experiment. it is called the layer blend modes:
Read more: http://www.2d-digital-art-guide.com/photoshop-layers.html#ixzz2lT8KaFdb