How to Sew an Invisible Zipper. An invisible zipper adds a professional touch to any sewing project. Unlike traditional zippers, they require almost no finish work. Invisible zippers require a specialized zipper foot, available at any store that sells invisible zippers. Here's how to sew an invisible zipper,
Lay the zipper face down on the edge of the fabric. Once you've cut out your pattern, pull out the two pieces between which the zipper will be installed. Lay out the two pieces, face up, with the zipper in between, so that you can see which edges the zipper will be attached to. Turn the zipper face down on top of the left piece of fabric and pin it to the seam allowance.
Sew one side of the zipper to the fabric. With the zipper unzipped but still pinned to the fabric, position it under the zipper foot so that the teeth of the zipper are in the "tunnel" to the left of the needle. As you sew, gently press the zipper against the center of the zipper foot. This will allow the needle to sew in the fold of the zipper.
Lay the zipper face-down on the other piece of fabric. Close the zipper and pin the free side of the zipper to the seam allowance on the other piece of fabric, lining up both pieces of fabric at the top.
Sew the zipper to the second piece of fabric along the seam allowance. Again, unzip the zipper, but this time position the teeth in the right "tunnel" of the zipper foot. Apply gentle pressure as you sew so that the needle will sew into the fold of the zipper.
Sew a seam from the bottom of the zipper to the bottom of the fabric. With both pieces of fabric face-to-face, match the edges and, using the regular foot, sew the seam from the bottom of the zipper to the bottom of the fabric.
Press the seam open. Keeping the zipper zipped, press the seam open as you normally would. Then, turn the fabric over and press the seam from the front, going all the way up the front of the zipper.
Don't be discouraged. Invisible zippers take practice. Once you get it down, you'll never want to install a traditional zipper again.