DEEP script: My first storyboard on photoshop

Hi again, finished the storyboard for Dereks DEEP script, my first storyboard attempt in Photoshop. I made a template for the boxes, then two layers titled 'grey' and 'black'. The grey layer was the basic outlines of the shapes and people within the soryboard while the black was the detail and final 'outcome'. I have yet to figure out how to draw characters onto a second layer on top of the background without the background showing through though, I'll have to ask a second or third year for some help with it.