In real rib stitching, the stitching is applied on the ribs in open bays. Stitching is not applied on sheeting. The purpose of the stitching is to keep the fabric attached to ribs, because the ribs do not have enough surface area to keep the fabric attached even with glue. The reinforcement tape is applied under the stitching to keep the fabric from tearing from the holes placed during the stitching process.

Here is video links showing the processes that should help you out.
This one shows the stitching process: http://www.youtube.com/watch?v=sCDTmy60R68

This one shows the covering tape process: http://www.youtube.com/watch?v=JgXd2...eature=related