On the previous page, You will notice that I have drawn a line on the underside of the vinyl sheet.
Turning a large sheet of Vinyl upside down and re-measuring to copy a line that totally matches the markings on the front is tricky. For a start, everything is Back to front. So what was right now becomes the left. Is it upside down?
A layer should never deliberately make a hole in the vinyl.
However, If you know there is a hole in the sheet vinyl, you cannot see it, and despite knowing precisely where it is, you cannot find it. Then Obviously, it is not there.


Two thumb tacks marked below and a line drawn on masking tape on the rvers side of the roll
I have inserted two thumb tacks that precicely follow my line. I pulled the vinyl back to expose the pointy bits. I then used these tiny pins to alighn my square.
Drawing a line (on masking tape) gives me the result you will find on the previous page