Originally Posted by
Onebyone
Glue basting to match my seams before sewing works for me.
That's what I do also, and here's how I do it:
Put your patches right sides together. On the top fabric, stick a pin in the very center of the seam (right between the fabrics), 1/4" away from the raw edge. Slide the fabric up the pin so you can see the bottom fabric, and stick the pin in the very center of that seam, 1/4" away from the raw edge. Put a drop of Elmer's washable school glue in the seam allowance and press to set the glue. Remove pin and stitch seam. If you like to press your seams open, simply run a stiletto between the seams to un-glue them.
One of the things I've discovered is sometimes, even if you use a 1/4" seam, you have to move one of the fabrics in or out by 1/16" or 1/8" to get the seams to match.