Creating digital art in Photoshop requires layers. Layers are like stacks of paper, some you can see through and some are opaque. Some art pieces have as little as 3 layers, and some have 70 or more!
Why are layers so important?
You can work non-destructively. This means you do not destroy your original photo or background.
Layers give you more creative control.
You can paint on a layer and adjust it (or delete it) as necessary.
You can decide how the layers interact with each other. Using blending modes opens up a whole new world.
You can control the opacity of any layer and the resulting effects of your piece.
You can work on top of your photo or background, and create copies of that photo or background to do additional work on.
You can create a layer mask on any layer to selectively adjust what you want or don't want to show through.
Each of the following photos are a result of 15 or more layers. Each layer has been worked on individually with blending modes, paint, opacity and other creative touches. Once completed I save the stacks of layers as a .psd or .tiff file so I can go in and adjust the piece in the future if I want to. I then flatten the image and save it as a .jpg file.
Mastering layers is a key to creating digital art in Photoshop.