I made the lacing strips today. The instructions were to cut an 18" x 5" piece of fabric.
I discovered that the bottom of a 12-pack of soda makes the perfect template for the lacing strips. It's exactly 5" wide and 16" long. After I traced and cut out the lacing strip fabric, I remembered that it was supposed to be 18" long and decided that 16" would have to be good enough.
Setting the grommets... Setting the grommets was a bitch and I'm only halfway through. I got one lacing strip done. It is really, really hard to cut through 3 layers of denim. The punch that came with my grommet kit was not up to the task. So I had to poke a hole with an awl (after making a trip to the hardware store to buy one), then force a phillips-head screwdriver through it to enlarge it, then cut the hole bigger with a pair of small scissors and trim the ragged edges so they wouldn't completely cover the grommet post.
My grommets were not lined up evenly at all, even though I marked the holes evenly. I spent the entire time vehemently swearing. My hands are incredibly sore and I know they will feel worse tomorrow, when I have to finish the other strip. I tried using a drill to drill the grommet holes, but after one hole realized that was a big mistake, because the drill bit just twisted the fabric fibers and distorted the seam.
Here's a picture of the shittiest grommet setting I could have possibly achieved. I don't think it could be worse if I tried. Whatever, I don't care as long as they will work for fitting the mockup. I hope I can do better on the final product.