I spent lots of time online learning about how to paint on glass worried about how it would work. What I learned is if you first block the whole thing out with white eggshell paint from the hardware store and then paint with craft acrylics the colors will show up more vividly and wash off more easily. I really sweated it ahead of time so this preparation of learning through all those YouTube artists who put their tutorials out there for free was almost like apprenticing. Here is the one I did on my dining room window. I let it sit almost a week and it washed right off.
I have tried to do the paper marbling to create more than just random patterns. Below you see a waterfall with green water below. I set it outside in the gravel to see if I could create a pop art landscape. The window was with leftover shaving cream that I just couldn’t throw out until I did just one more. I used a Squeegie and dragged only an inch each time. Instantly it looked like a window. I have purple mums that are showing their best color right now and I thought it was a pretty picture. I love pictures of windows. The birds I did by picking up swirls of color with my thumb and laying them on. The purple flowers with yellow centers were done with a plastic bag I scrunched up right and dabbled.