Hi Joan - two things to try
- add starch to your process - I starch my fabrics before I cut - this makes the fabrics really behave
- I use a tailer's awl to hold the seams together right until the seam gets to the needle; I don't pin, just place the seams together as I'm going, then stick the point of the awl into the intersection and keep it there until it gets to the seam. You can still do this if you pin - when you take the pin out, stick the point of the awl in the intersection again right until it gets to the needle.
Hope this helps!
Linda