Using the Layers window in Photoshop

The Layers window shows the various layers that your image is made up of.

To make a new layer, click the New Layer button, as shown by the red arrow.

To work on a different layer, click on that layer. The eyeball will apear next to that layer.

You can drag layers up and down the list.

Note – create a new layer for each part of your image. More you need. This allows you to go back and edit the layers individually and you can modify easily. Every Adobe Photoshop beginner at some time makes a masterpiece, only to find out that they did it all on one layer, and now they can't remove those pink clouds they put on it. 

The Layer in Photoshop.