I was thinking of black set in triangles on the edges to get it straight. Then a black binding. Or any color that would look like a background not part of the zig zag.. That way you only deal with straight edges to finish off.

Makes for a pretty quilt.

Oops! I'm sorry - I missed the first sentence where you said you already made it!

Can't you just use binding? You can just sew it on and make both inside corners and outside corners. It will look nice with the ends left on.

Not to repeat myself (but I will) - it is MUCH EASIER to do facing than any other option, and it looks better too.

I am glad to see that I am not totally crazy!