When I open the box and find my new ARF has wrinkles or air bubbles in the covering I first try to find out which brand of covering was used. Each brand has a slightly different recommended application temperature. So I adjust my iron to that temp. If you cannot determine the brand of covering, or it is a non-name brand, then start off at a lower temperature, (just to be safe). Slowly raise the temperature until you begin to get the results you want.

I also take a "T" pin and sharpen it. I use this to make tiny holes in the covering over the air bubbles. Typically the bubbles are long and narrow. So I would ***** the covering with my pin every 1/8 of an inch or so down the length of the bubble. This will allow the trapped air to escape so the covering can be tightened and the adhesive can stick to the wood.