all you have to do now is put the bladder inside it, and use it.
Step 5: Insulation continued
now put the liner inside the jean "sock". it should fit snugly inside the sock, with no edges protruding. squash it flat, and then stitch one corner of the sock to the liner. whe this is done, stitch the diagonally opposite corner together. this should be enough to stop it falling out.