Check the accuracy of your cutting AND your seam allowance.
Also, when you are sewing and get to the area of the point, you can slow down, and make sure the needle is not going into the point. I thought I just saw some suggestions on one of the shows, but I don't remember which one. (I rarely watch the shows as soon as they come out, and I'm always going back and watching the old shows... so I don't keep track of the tips I see from Ricky and Alex.)
Diane in Colorado Springs