Find images to cut (I just used the ones in Cricut design space) and reside to .2 inches less than the max width of you flashlight.
Repeat for the outside decoration. I found the cute Trick or Treat just by searching “trick or treat” in design space.
Cut from either vinyl or window cling. Window click will be more transparent but since you are leaving a .2 inch border there should still be plenty of light either way. In my pictures the black is vinyl the orange is window cling.
Weed (remove negative spaces) and position your cuts on the flashlight.
Notes
I think these flashlights could be way for all different kinds of occasions.