Step 1: First, I needed to make sure my sweater was going to be big enough to cover the down pillow. Here's the down pillow with the old cover.
Step 4: Place the sweater pieces, right sides facing, around the outside of 3 sides of the square with about 1/2" seam. Leave one side open for inserting the zipper.
Step 5: For me this step was salvaging the old zipper from the other pillowcase. If you are doing this too be careful removing the zipper anddo not let the zipper slide get near the ends of the zipper and become detached. In fact, if possible I highly recommend that you sew the ends of the zipper on either side together to prevent the slide from coming off all together! They are very hard to get back on!
Step 6: Once you have your zipper ready, use your zipper foot to insert the zipper on the open side of your fabric. If you are unsure how to insert a zipper you can find a good tutorial at http://www.threadsmagazine.com/item/3728/sewing-in-a-zipper.
Step 7: At this point I turned my pillow case inside out and sewed the corners of the unfinished side just up to the zipper to give it a more finished look.
Here is it all done! It is a nice addition to the other comfy pillows on my couch!
Hmmm...what to re-purpose next? Ideas?