Removable Padding Sliding Around...

The padding pillows are sewn out of Lycra and stuffed with Polyfil. The legs are fitted and tailored to the padding shape, so the pillows aren't slipping around because of the suit's bagginess. The pillows are well-stuffed and big enough, so it can't be because they're too small. So it must be because the Lycra is so ridiculously slippery. The padding slips in every direction and won't stay in the right position.

Does stick-on fabric Velcro work? How about elastic straps sewn into the legs?

Thoughts? Please let me know if you have an idea. Thanks!