Decoupage Glue Recipe

I have used equal parts of water and regular white glue to decoupage paper to something else. For a recent project where I was adhering cloth letters to wood, I used the decoupage glue and did not water it down. I "painted" 2 layers to make sure they stuck!

Tin and plastic should work. I did cancelled stamps on tin plates once. I would be careful to wash the plastic in Dawn to be sure there is no grease on the surface.