My mom has a very tall tree with a large branch span at the bottom. The bigger pattern is for her. It's about 2.5 feet from the center to the edge. As you can see, the hole at the center is much larger than the one for my little tree.
I recycled used wrapping paper to make the larger pattern. I wrote instructions on it for my SIL who plans to make one for her tree next year. So if you have a big tree, haul some of your wrapping paper out of the recycle bin and flatten it out. Tape my little pattern down and extend the straight lines with a ruler. Use that same ruler to mark your bottom curve.