Yes I do have a plastic putty knife. The problem is that the contact paper is so sticky that is really sticks hard to the metal in places where you dont want it to stick yet. Then, after you pull it up in that place, it stretches out and gets even more bubbles.
I wonder, since it is metal, if I could spray a mist of soapy water (like doing window tinting) and put it down, but I am scared it will make the glue not stick anymore.