I’ve been teaching pants fitting and sewing since the 1980s. My techniques and skills have changed and improved over the years, but this fly-front zipper technique has remained the same for me because it works. It’s a classic technique I learned way back when, and I’ve enjoyed carrying it forward into new decades. My students feel proud of their zippers when they use this method—it satisfies the sewing geek in all of us.

This method is adaptable for any pattern with a center-front seam, as you can draft your own extension or modify an existing one. Each step has easy preparation to get the elements in proper alignment for stress-free sewing. Along the way, there are opportunities to catch any mistakes before you proceed to the next step. And it relies on some basic physical guides, like clear tape, zipper tape, and carefully placed pins, to guide your topstitching. The finished result only appears to have been painstaking.

If you’ve never tried sewing a fly-front zipper before, I am certain you can follow this tutorial. You’ll be amazed at how simple it is. If you sew them all the time, maybe this easy method will offer a refreshing, relaxed take on a traditional closure.

Plan or modify an extension

Some patterns come with a fly-front extension drafted onto the pattern, while others have a separate piece that gets sewn to the center front. Regardless of how your pattern looks, here are several tips.

Fit the pattern first. Use your preferred fitting method, or work with a pattern or sloper you’ve already modified for fit. Assess the proper rise, and determine how you want the pants to sit on your body. Rise styles change and, right now, we are seeing a higher rise in fashion.…