Stitch Example: Flat Piping Seam

Iron the bias strip in half. You don't have to use bias, but I did because that's what I had cut.

Pin the bias to right side of one side.

After stitching, press.

Pin the second side of the seam, so right sides are together for the fabric and bias tape is in the middle.

Press after stitching.

Grade the seam allowance if you like.

Now press the seam to one side. At this point you could also top stitch on the upper side if you wanted to.