I put vinyl graphics from RotorGraphics on my helicopter canopy. They recommend using 70% isopropyl (rubbing) alcohol to wet the vinyl for positioning. Put it in a spray bottle, wet and apply. It worked great and dried fast.

Here is a link to their website. Click on TIPZ on the left side of the page.

http://www.rotorgraphics.com/

WARNING: I have not tried this when applying to iron on covering.

Eric