BTW, the gun is by far the fastest, safest, and best shrinking tool.

Once the seams are stuck down for sure.....

It is real easy to put exactly the right amount of heat on the covering with a gun. Start with it "too far away" from a loose, wrinkled area. Bring it closer until the wrinkles shrink. You've just discovered the distance the gun needs to be to put the right amount of heat to the work. It's worthwhile to only put that much heat on the job. Too much heat can burn through.

As soon as you've found the right distance and that area has tightened up, start moving the gun. It's a waste of time to dwell over "finished work". It's also risky. So start moving the heat. As you move it, you'll notice the new areas of covering respond. You'll now be able to figure how fast to move the heat.

You've got a safe distance, just the right amount of heat, and you're moving just as fast as the covering will allow. Ain't nothin' can do better.

But seal the seams first with an iron. A gun can't do that job worth spit.