I've done a few planes with a skin by rasterize, so allow me to tell you how I did it.
Step 1: You need to print out the skins to scale. In the case of the mini mustang, @Rasterize
has formatted them to fit on 11x17 sized paper, which is a common printing size known as "tabloid".
I have had the best experience saving the skin PDF files to a flash drive after downloading them and then taking them to a UPS store to be printed. Usually the staff there can help you make sure that it's printed to scale.
Step 2: Once your skins are printed, you need to carefully and accurately cut them out with a pair of scissors.
Step 3: Regardless of whether you're working with a scratch build or a FT kit, you need to get your foam airplane pieces punched out and ready to assemble. When you're done with this step you should have a pile of white or brown aircraft parts and a pile of printed skins.
Step 4: Starting with the most obvious pieces (for example a rudder/vertical stabilizer) peel the plain paper off of the foam, and replace it with your cut out skin. You can either use spray glue to attach the paper to the foam, or I have had great success with a simple glue stick.
Be careful when doing the wings that you do the top skin on top and the bottom on the bottom. This can be tricky as the wing isn't assembled yet and it's easy to get turned around. The skins are very realistic so they don't say "top" on them or anything.
Step 5: Assemble the aircraft as you normally would following the FT video. Be careful doing bevel cuts, as the new paper covering is a little thicker and more difficult to cut.
Step 6: Enjoy your awesome looking plane!