A right curve cut template which has the tailored curve on the left side is used for a cover from the left to the right. The left curve cut template logically is used for a cover from the right to the left.
A curve cut-cover for the roof is set with an app. 45 degree inclination, a curve cut cover for the wall is set horizontally. Here you will find a requirement list and on this bases you can find out, which measure is right for your roof.