do you pin the seams to nest? I find that I get better results if I pin just on either side of the nesting seams. And I try to always have the seam that points toward me on the bottom so that the one that I can't see is pressed down by the presser foot. The one that is facing away from me I try to keep on top so I can make sure it' doesn't get flipped by the presser foot. Does that make sense?