I turned my thigh-high leg warmers for Nora Valkyrie into tights, and I filmed it so you can do it too!
need...
thigh highs (or leggings, or boot covers, or another pair of tights, etc.)
dance tights (or leggings)
scissors
pins
preferably a serger. this might be possible using a stretch zigzag stitch on a regular machine.
also I apologize for the occasional terminology mix up, filmed this on the fly after work.