Butterick 6031, my lingerie pattern. (See the slip steps in these posts.)
Before we start, perhaps you're wondering, "why the heck would I make my own panties?" Let me tell you, the reasons are numerous. After you make one pair of these, you can tweak the pattern to your personal preferences. I designed these to be my perfect undies: boyshort-esque, with adequate butt coverage, flat lace trim, and a higher-than-usual rise (though not Bettie Page high). The design came from my frustration at finding lingerie I liked the fit of. Second was my frustration at the cost of lingerie. $23 for a pair of panties that rides up all day? No, thank you. Once you get the technique down, you can make a pair of these in about 20 minutes and the cost of supplies is incredibly economical.
Convinced? Okay! Let's get started. First, make sure you have a stretch needle in your machine.
You'll have three pattern pieces cut out: the front, the back, and the lining. You'll also need a length of wide stretch lace trim.
With right sides together, sew the front to the back at the crotch seam: set your machine to a narrow zigzag (about 1 mm wide by 2.5 mm long) and stitch with a 5/8" seam allowance. Then stitch again with a 1/2" seam allowance. Trim next to your second line of stitching. Finger press the seam allowance toward the panty back.
Get out your lining. Place the lining over the crotch seam, on the wrong side of the panties. Pin in place.
Now get out your stretch lace. On the upper edge of the panty front, place the lace on the right side so that it's overlapping the edge of the panties by 1/4". Pin in place. The lace should not stretch at all as you're pinning or sewing it.
Stitch in place close to the lower edge of the lace with a square zigzag (2.5 mm x 2.5 mm).
Repeat with the upper edge of the panty back.
Now open out the panties and repeat the lace pinning/stitching process with the leg openings. Here's how it will look pinned.
Hope you enjoy! Now go forth and make panties.