I put mine into a plastic bottle and have always used it from there. I guess I should read the directions too because I have used it for years without any problems, and I love the stuff. I just got a new tube so will check out the directions!
Wonder if that will change how I do it? I have put it in a plastic bottle now for a long time because the tube got ruined after using it for a while, maybe that is why you have to heat it up with water?