I didn't know this how-to when i made these, but it's totally what i did, so it's even a version :)
I used child's pants, so that's why i can put them only under the knees.
From old pants to Awesome Legwarmers and enough extra to make shorts or something
Keep your legs toasty!
Make a pair of legwarmers to match any outfit!
Moonwalking to awesomeness!