For visual learners, this video from Lauren's Top Tops shows the standard centered zip method, while this video from Professor Pincushion covers the process of installing a zipper in a seam. To make sure this fits your project, are you: (clothing) or a bag ?
Installing a zipper, or a separated (like a jacket) one? Let me know, and I can tailor the instructions further. Install a Zipper in the Center of a Seam lb.zip
If needed, create secure bottom stops by stitching across the zipper teeth multiple times to prevent the pull from coming off. For visual learners, this video from Lauren's Top