A made this a while back but wanted to share. 
I planned to do this years ago, when we first bought our house, after I learned about this product called Gallery Glass that simulates stained glass.
I drew the design out on a large sheet of paper, which I covered with wax paper. After everything was taped down, I drew the design out using the black gallery glass liquid leading. Then, I filled in the colored sections. The wax paper did stick a little bit, but I was able to peel the wax paper off and get rid of any excess with a sponge and some gentle scrubbing.
It didn’t turn out perfect; things got kind of crinkled and my design didn’t end up centered or symmetrical. But, I really love how it turned out. I love sitting by this window and looking outside. I do wish the material stuck a little better, but for the most part it clings to the window just fine.
I wonder if it would have worked better if I’d applied the design to a different backing material while it dried. Although, the random un-stickiness might also be because we have such extreme temperature changes where I live. Midwest Canada gets reaaaaal cold.
There is a plastic/acetate that is offered by the brand that makes Gallery Glass, but I needed something especially large for this project, and some of the how-to’s I read suggested using wax paper as an alternative.
