I'm learning how to edit double exposures and it is rather tricky (especially since I don't have Photoshop)--but then all of photography is. Photography is the art form that seems deceptively simple; you pick up a camera, push a few photos and voila: a photograph! It seems simpler than painting but a good photograph is the same as the difference between finger painting and a Monet. I don't want to compare the photographs I take running around with my tripod and remote to a Monet--or in the field of photography a Brassai--but I do strive to improve my photographs and have come a long way from the images I snapped with my little digital camera hanging off a tree branch in college (side note: this method is highly unadvised it is how I eventually broke my first camera!). Part of the growth is acknowledging that photography is a skill like any other that requires practice and patience; patience to always be a beginner and not just stick to what you know but explore new ways of using your camera and learning from others, and practice. There is simply no replacement for putting the time in and practicing your desired skill. So my double exposures (and long exposures!) have a ways to go, but I'm learning.
*pictures by me*