This is an old thread, but since it comes up once in a while (and since it’s been discussed that disposables aren’t environmentally the best choice for mother earth or for your plumbing), here is my solution for the non-water soluble make-up: Dawn dish detergent plus a squirt of liquid laundry detergent plus a squirt of stain remover, rub it in, let it sit for a couple of hours, & launder with Oxyclean. This was just an experiment to see if I could do it. I’m not sure I would go to this extent every time. I have a basket of gray washcloths with a little sign that read’s “For Makeup Removal”.
Take a picture, throw them in the rag bag and send the guest a bill for new towels.
RR