Whew, what a SLOW sewer I am!! Each step so far has taken me two rather than one hour. Some have taken more. But I have persevered and have now reached the point where I see what I'm making. Up until now I've been good about not looking ahead, but I'm afraid the instructions will disappear, so I peeked at the last two steps. With all those little triangles, I was pretty sure we had a sawtooth border. I'm not going to push myself now, but will definitely finish this week.
This is a pattern I would have said was beyond my ability, but it has been fun to follow the instructions, and I will say that I'm happy with how my corners have turned out. They're not all perfect, but the learning experience has been good.