I put putty zimmermitt on my paner IV H to day ,this is how i did it i put tape where idid not want the zimmermitt, then i put the putty on with aold credit card and has i tryed to smooth it out it was not smothing, and i added model glue but i finally got i t to smooth it looks ok for my frist zimmermitt job

Hey Old credit cards, That's a good idea I think. I always those babies should have another use besides get myself in debts.....

Generally, I just use a spatula to apply them then smooth out with my fingers....