Hi, I took a tip from a really smart woman that has turned out almost perfect seams everytime. After you nest your seams together use Clover Patchwork Pins to pin on each side of the seam line securing the seam allowances with the pins. When you sew and approach a pin let your needle come down catching first seam allowance, remove that pin, sew over the seam and than remove your other pin. Hope this makes sense. But my point is, I have used every pin for pinning and these are the absolute best for matching up seams. So good luck to you. C.