Do as
@mamajulie and seriouslyo?erbooked suggest. My wife did that for our son a couple of years ago on a black pair of dress pants and it worked great. It was on prom or homecoming night (I don't remember) and right before he was leaving he knocked over a candle and the wax spilled onto his pants. Needless to say, there was a mad dash to clean it off! Good luck! 4951