My little girl is rapidly outgrowing her legging so I decided to make her a few pairs that won't squeeze her like the store bought ones (I didn't photograph the other pair, sorry!). I used an old pattern for the leggings and I added a little flair at the ends to make these legging look a little more girly. I really love the fabric (bought at Girl Charlee's) but the colors are dark (grey-green and brown) and not very girly.
To make the bottom piece I just cut out a strip of fabric twice as long as the bottom width and 3 inches tall. I used a gathering stitch and gathered the fabric evenly and used my serger to attach it to the leggings bottom before I sewed the side seam. I believe I used a 5/8" seam allowance because the ruffle was a little too long for my liking. After I attached the ruffle, I pinned and serged my sides together. It was a quick and easy modification that makes these legging look a bit more feminine.