I needed a 22" navy blue invisible zipper, so I went to my local JoAnn Crafts and Fabrics. There was no 22" navy blue invisible zipper, not even a 16" navy blue invisible zipper, so I bought a regular zipper. Yes, I could have purchased another color because only the zipper pull would be seen, but I'm too obsessive for that. I hadn't inserted a conventional centered zipper in ages. When I did, I basted the center back seam, pinned the zipper over the basted seam and sewed it in from the right side. The pins sometimes prevented the zipper from being sewn smoothly, so I thought this was a good time to try something different. I found this method in The Sewing Book (Smith, 2009). It uses more hand basting than I'm used to, but I have learned to "embrace the baste."
I realized I've become too dependent on invisible zippers and I decided to work on installing conventional zippers. I was never completely satisfied when I inserted centered zippers the "old" old way. Even using this "new" old way, the zipper teeth show a little more than I'd like. But then I'm used to invisible zippers where the teeth don't show at all. There is a slightly different method in The Illustrated Guide to Garment Construction (2011) that still involves basting the zipper tape to the seam allowance. Installing zippers better is a worthwhile goal for me. It gives me an excuse to buy Bernina's zipper foot #14, which has a guide to insure straight top stitching when inserting the zipper. Both The Sewing Book and Garment Construction were originally published in the UK. Maybe this is the way zippers are done over there. This method takes a little longer, but I'm willing to sacrifice speed for a neatly inserted zipper. I'm sure the time will come again when I can't find the invisible zipper I need at JoAnn Crafts and Fabrics.