Normally I use either Model Masters or Tamiya Acrylic paints. I have found that Krylon Spray paint works well for large areas, and in places that could potentially chip, crack, or flake due to movement. For this I used a Metalic Silver Sharpie
. I sacraficed a C-3PO by spray painting him and wasn't happy with the way he turned out. I couldn't keep the glowing eyes feature and I didn't like how the paint dried around his eyes so I went with the Sharpie instead. All I have to do is get a coat of clear spray paint on him and then he is done.