Step 4: Trim your center square
Now, the whole idea of a crazy quilt is that it is off-kilter and nuts. So you don't want to just leave the center square to be, well, a square. Use your ruler and cut some fun angles into it.
I would, however, caution you to actually use that ruler and get super straight lines. The reason that this crazy block is so simple is because it's all straight lines!!
When you get this piece trimmed, place it on the muslin square, face up. Try to keep things, once again, off of center. Also maybe think about how the angles that you cut into it may effect the look of the finished piece once it spirals out.
Pin this in place, and you'll finally be ready for some sewing. :)