How to shave the edges of roll-ups
Get yourself an X-acto knife
Put the film on as you usually do. W hen you position the film on the glass at the top edge, bump it up so it is past the top edge. About a 1/8 inch is enough. Now to start the process you need to remember 45 degree angles These angles are very important! Now take the blade and start at a 45 degree angle to glass. Then turn knife to a 45 degree angle. And then a 45. This gets confusing when trying to explain it so I will get pics. The cut is done on an upward stroke. I have never had one peel back on me yet. Give it a try it is really fast and looks great. When all angles are at the 45's and you are cutting you may need to adjust more or less angle for the depth of the cut. Less will give you a deeper cut. Hold the blade gently and use upward strokes. If you're getting jagged edges adjust your angles a little but usually the 45's are about right.
This is the first 45 angle
This is the Second 45 angle
And the Third