Easy as pie. Place vials in a small pan of cool water 1/4 - 1/2 inches deep. Aerate vials with a new needle, placed so that the needle is not submerged in the oil, but just penetrating the rubber seal. Heat on LOW for 5-8 minutes, MED-LOW for 5 minutes, then MED for 5 minutes. Remove from heat, cover, and let sit overnight. Crystals should be dissolved. I usually put a sterile 2"x2" swab over the rubber stopper, put the plastic cap back in place as best I can, then tape it tightly over the rubber stopper. No problems to date, Prop still works like a charm ;-)