I love Mylar. It’s durable, smooth, translucent, and accepts media beautifully. Here’s a little abstract done using oil sticks. The sticks are essentially oil paint with extra wax. The sticks form a film or skin which you need to cut or peel away, and then you can use the gooey and smooth paint inside. Apply thick or thin onto Mylar, using any tools that are handy: gloved fingers, scrapers, J-cloths, paper towels, etc. Add other media like graphite, alcohol to disperse paint, markers, etc. Lots of fun!