I've been thinking about making my own leggings for some time. I just didn't want to do it with my regular sewing machine. Certainly it can be done, but if you have a 4-way lightweight stretch jersey, it'll take twice as long to sew. Having a serger really is a game changer for me. I whipped up these pants in just over an hour, including making the pattern. I had some leggings that were getting threadbare, but I really liked the rise and the fit, so I sacrificed them for the pattern. I simply cut carefully along the seams and laid it out flat. Since cutting out the pattern, I no longer had seam allowances. I didn't want to manually measure all of my seam allowances so I made up this little trick. I'm sure it's been used before, but maybe you can benefit from my funny little discovery? Tape three pencils together, keeping the middle one higher than the other two. It's just 1/16 shy of 5/8 inches. Not shabby. Not shabby at all. I sewed everything in a slightly different order than the leggings that I made for Felix, and I like how it went. It was a bit easier:

1. Sew front rise right sides together
2. Sew elastic to the wrong side of the fabric(you might need to stretch the elastic a bit during sewing)
3. Roll the elastic down
4. Sew the back rise, right sides together (including elastic!)
5. Sew the legs closed, right sides together
6. Finish hems

These leggings feel like pajamas. You'll definitely see me sporting these at Alt Summit this year. And here are some legging tutorials if you're interested in making your own: Baby Leggings Tutorial & Pattern • Basic Leggings •Printed Leggings • Ruffle Bum Leggings • Ruched Leggings • Making Leggings