Types of Buttonholes Square: Your standard, square buttonhole. Rounded: For lighter weight fabrics. The diagonal stitches on the rounded buttonhole do a better job of securing themselves in the looser weave of the fabric. Keyhole: For heavier fabrics. The keyhole shape allows the butt...Next up in the index card tutorials is the invisible zipper! While it may sound intimidating, in my opinion it is actually the easiest and quickest to install once you get the hang of it. Instructions: Note: Insert the invisible zipper before sewing up the rest of your seam. Step 1...In the continuing zipper saga, this month's Index Card Tutorial is the lapped zipper - that vintage fashion staple that comes in handy in both my garment and home-decor projects. Instructions: Step 1: For this zipper, it may be easiest to give yourself a 1" seam allowance, as it makes i...