"This is my method as well. Then once it is all pinned, I smooth outward with every seam I sew. Good Luck!" quote from Challys
I do this, too, but I actually take the quilt off my machine and smooth it all out again and again and repin. It takes time but so does doing the "frog" - ripit, ripit. Hope this helps. You'll get it right - it just takes time.