Just curious if this would work. I'm not sure that I trust my hand at folding properly to avoid that dreaded V at the folds.

What if ... I cut the fabric to about 3" of the fold (or folds if at both ends), then opened the fabric up and using the edges I already cut as a straight line - finish cutting the now 6" that sat in the fold. Would that work?

Can you mark the fabric with light pencil marks as a guide - and then use your ruler to cut - sometimes moving the fabric is the best way.

Well, I got the fabric cut (and project finished). I never did found a "perfect" way to cut the long strips. LOL But the pencil marking of the length and using a ruler to rotary cut was the best method. I didn't try to cut it folded because it was a satin and keep slipping on me. I anchored the remainder of the fabric so it wouldn't slip off the counter top.