For pieces that cover cross as the figure below (AB = BC = CD = DE = EF = FG = GH = HI = IJ = JK = KM = MA).Use the clamp and cut the two parts back to be a rectangle has length twice the width.
Plus cardboard image for as pictured below (AB = BC = CD = DE = EF = FG = GH = HI = IJ = JK = KM = MA). Please use two cuts and put the pieces back to form rectangle with a length double the width.