carefully cut the lock hole out of the backing paper w/ razor blade, this will help you line up decal.
use water w/ some dawn or similar dishwashing soap.
clean panel, spray w/soap
apply decal, while wet and you should be able to move it and line it up if needed. squegee water from decal with plastic knife (ones for bodywork-bondo work well)
you can let it dry with top paper on and remove when dry.
be careful removeing top paper and watch to insure decal stays where you want it.
good luck