I cut my 9x9 just like NCPatrick, then I drew a parabola from there and up making the curve 11 inches or so from the cut which curved around the parabola. The curve terminated at the points or corners left from cutting off the triangles. I used bias tape to edge the cat cut and added loops. When I got done though I felt like I had taken too much off the tarp to give me the coverage I needed.
It now weighs only 17 ounces and measures 29 inches to the apex, the shortest width from the ridge line. Before I cut it when only the triangles were removed it was 38 inches to the ridgeline. So now in the middle of the tarp I only have 29 inches per side where I need the coverage the most. Now that is perhaps as much coverage as the stock HH tarp offers, but.....
Well, &^*# happens.
But to get some perspective on the size of the tarp I got out the stock tarp for the Claytor and layed the Sportsman with the cat cuts on top or the original Claytor. I was amazed! After putting the cutoff sections in place it was easy to see the starting sizes were identical, 9x9 on the Claytor AND the Sportsman tarp.
I left the Claytor alone. If I ever do cat cut it I will only go up to within maybe 7 or 8 inches BELOW the seams that hold the triangles on.
The Claytor camo is so pretty, I am glad I am back to it.