This howto is part of my <a href="http://www.cutoutandkeep.net/projects/messengerbag_with_painting/">Messengerbag with Painting</a> project.
I made two zippers: One for inside the bag, and one outside. I'll show you the one that's on the outside of the bag.
I'll try to explain this in english.
First, you take one piece of fabric you like for the outside.
( I glued a piece interlining on it, so the fabric would be stronger)
Then you take a piece of interlining and draw a rectangle on it that is a little bit shorter than the zipper.
(Like the light lines)
And in the middle of the square another line and on the sides a triangle
(Like the darker lines)
(This is not a new zipper I bought, but I cut it out of an old sportbag)
You take a piece of another fabric you want to use for the inside of the zipper-bag.
and stitch it with the piece of interlining like this
!Only stitch the purple rectangle!
Make sure the piece of fabric is not in the middle of the fabric of the zipper-bag (below)
This will become the zipper-bag.
And the black fabric is going to be the big messengerbag.
Now you cut the black lines and fold and pin the sides like this.
Then you sew a rectangle, so it will look like this
Sew the zipper in a rectangle on the fabric.
Then sew your other piece of fabric(dots) for the bag on the other piece(dots).
!Don't attach it to the black fabric!
Your zipper-in-a-bag is finished!
to see how you make the messengerbag*