Here is a link for making the easy attic window. I would suggest you measure your panel & decide how large you want each section to be cut. Choose a number that you won't be wasting too much of your panel. Lay it out on the floor & place your "window sashing" fabrics & make the little corners & stitch together row by row.
http://www.straw.com/equilters/libra...ticwindow.html