Now that your cording is attached to the main pieces of your cushion,(cushions part 1)it is time to add the banding.
Take one long strip that you already cut out for the cushion. It should be the length of the fabric (about 54-60") and however high the side of your cushion is plus the seam allowance. Wrap it around the sides of the cushion. You want to make sure that it is long enough to go around 3 sides. The fourth side will be the zipper. If it is not long enough you will have to add partial pieces to each side to make it long enough. See second and third pictures.
whenever I sew two pieces together I iron the seam allowance to one side and then top stitch. It makes the seam stronger.
Serge your edges.
Get out your zipper tape. Mine comes on a roll like this one.
Take your two zipper sections and serge down the one side of each piece. Take your zipper tape and zipper foot and sew down the serged side of your strip. Iron flat.
Take your other strip of fabric and iron over a 3/4" hem on the serged side.
Lay the ironed side on top of the free edge of the zipper.
Pin in place.
Top stitch making sure not to sew over the zipper teeth, but catching the edge of the zipper tape.
Take your zipper pull and slide it down on the free end of your zipper.
Now, go back to the long piece that is for the front and sides of your cushion. fold it in half and put a pin at the fold.
Do the same thing with your cushion piece (that has the cording around it) on the side that will be the front of your cushion.. Take the pin of the long piece and the pin of the long strip and match them right sides together.
You are going to pin around the front and side pieces of your cushion working both directions away from the two pins you just matched. This makes sure that your seams are at the same place on either side of your cushion. Do the same thing with your zipper section, only matching the pins on the back side of the cushion. As you pin away from the matched pins, you will meet the side of the long front section. You can see from the picture below that I have a little bit of length left over on the long front section. I will cut it off in a minute.
Once you make sure it is matched you can cut the extra off.
When you sew the zipper section to the other front strip, use a little piece of fabric to cover the zipper teeth. It will keep you from breaking your needle and help the thread not to rub directly against the teeth and break.
Top stitch your seam and do the same thing on the other side.
Sew all the way around the cushion.
Once one side is on, all you have to do is pin the other piece of the cushion to you free edge of banding.
When you match the two together, make sure to start at the corners and ease any extra fabric in on the sides. If you don't start at the corners, the bottom and top pieces of the cushion will not match and your cushion will look twisted.
Repeat on all of your cushion pieces. Turn right side out and add your cushion. Please don't be discouraged by the amount of work. You are over half way done, and the fitting of the body of the couch goes much faster!