I was asking the same question and found these instuctions as follows...
also see link here..
link..http://www.ehow.com/how_5828690_fix-tear-polyester-fabric.html
Instructions
Things You'll Need:
* Fabric for patching (matching color and comparable weight)
* Scissors
* Pins
* Sewing machine
* Matching thread
1.
Step 1
Cut the fabric so it covers the tear completely with approximately 1 inch of excess fabric on all sides of the tear.
2.
Step 2
Position the fabric on the back of the polyester fabric so it is underneath the tear. Pin the fabric in place.
3.
Step 3
Line up both sides of the tear so the tear is flat over the fabric beneath it.
4.
Step 4
Set the sewing machine to a wide zigzag stitch and begin sewing a zigzag stitch across the tear. Make the zigzag stitches close together to cover the tear completely with stitches. Stitch along the entire length of the tear. Make one or two additional rows of zigzag stitches to cover the tear completely. This will ensure the tear is securely closed.
5.
Step 5
Turn the polyester fabric over to the underside and trim away the fabric patch approximately ¼ inch away from the zigzag stitches.
sewknit&fix, February 2010
