Whether it’s linen pants for summer or wool pants for winter, some pants are nicer lined. The lining makes it easier to slip pants on and off and gives the body a smoother silhouette. It makes the garment fabric more opaque, less clingy, and more comfortable. Lined pants often last longer than unlined ones and are a hallmark of better quality. And here’s the best part: Lining pants is easy. Start with a pants pattern that fits you well. I’ll show you how to choose fabric, how to make a pattern for the lining, and how to construct and attach it to pants with either a fly front or a center-back or side zipper.

Prep the lining 

Make minor modifications to the pants pattern to create the lining pattern. 

1. Copy the front and back pattern pieces only. If smaller pieces, such as a side front or other pocket pieces, are needed to complete the side seams, attach them to the main pieces. Fold in any front extensions, such as a fly facing or pocket extensions. Fold up the patterns along the marked hemline. 

2. Cut the lining. Pin the modified pattern pieces to the lining fabric following the basic pattern layout and marked grainlines. Cut the fabric from the pattern using the standard seam allowances and cutting lines. 

3. Transfer markings for darts or tucks. For fly-front pants, mark the zipper opening 1 inch below the mark indicated on the pattern and transfer the fly topstitching line. For a center-back or side zipper, mark the zipper opening 1⁄2 inch below where indicated on the pattern.

Assemble the parts 

With minor exceptions, follow the pattern instructions to construct the outer garment, including darts, pockets, seams, and zipper. The lining construction is basic. However, the order is slightly different, and some seam allowance…