What I have learned (and you probably already know):
-Wear a mask or just hold your breath while you spray paint. Headache will ensue if you don't. This shit toxic. Also, you will feel something weird in your mouth or throat for a couple of hours.
-When spray painting cardboard, prep with a layer of lacquer, fixative or whatever the guy at the craft store recommends...this will guarantee that you will see the color you see on the spray paint canister can be replicated on the cardboard.
-Protect the area you will be spray painting on...or you will find nice permanent paint where it wasn't suppose to be. I knew that but I just didn't protect a wide enough area. Gold balcony is sexy.
-If you leave your pieces to dry outside and leave the house to play...don't forget to anchor things down or you might not see your stuff ever again. I'm happy the BBQ grill was in the way preventing the letters from flying off our balcony. It wasn't even that windy ...