Installing an Invisible Zipper
Gather your supplies. Your fabric, zipper, concealed zipper foot if you have one and tools. This next step might not seem like much, but it is essential to getting the invisible zipper correctly installed. Iron the zipper teeth FLAT with the iron set to a synthetic setting and the zipper unzipped. The flatter they are, the more successful you will be. Also note that you do not want to rezip the zipper at any point before installation is complete, as it will cause the teeth to curl up again and undo all of the work you just did in flattening them.
If you're installing the zipper in a woven garment, finish your raw edges with a zigzag or overlock stitch. This will ensure the fabric will not unravel overmuch as you work. After you've completed that step, make a mark along the raw edge at the distance of the seam allowance. This will help you get the zipper placement right. Do this with tailor's chalk or a disappearing pen on the right side of the fabric. Make sure you mark down both the left and right sides of your opening.
Typically speaking, most concealed zipper garments are lined, so make sure you keep the lining out if the way here. This is JUST for the main fabric piece. Take your zipper and lay it face down on the right side of the fabric with the teeth lined up along the line you made previously. Keep the raw edge of the zipper to the side with the raw edge of the fabric, as pictured.
Now, with your concealed zipper foot (or regular zipper foot if you don't have one) stitch right along the zipper teeth. Be very careful not to catch them up in the stitches!
Now Do It Again!
Now that you have everything all stitched down on one side, you're going to repeat it for the other side. Pin the other side of the zipper to the other side of the opening and stitch close to the teeth again.
Your zipper is installed! Now, in a lined garment, you'll still have to deal with lining, but if you follow the pattern instructions, it should be pretty easy. The hard part is all done! And look how pretty it all turned out!
I hope I helped explain it all sufficiently, but if you have any questions, please comment them below or visit our Facebook group. We're here to help!