Take a look at Deb Tucker's youtube video for her flying geese ruler. She also makes them a little oversized and then trims - however - I was trying to make some and had already cut pieces the exact size, so I used her tip of putting the squares slightly inside the corner, and it makes a huge difference. They came out really well. Of course, I already own the ruler, but was just fooling around and didn't get it out. I definitely will for the next batch.