Use the very thick Oral Balance product from Biotene. Before sleep squeeze some of it out of the tube and onto your tongue, then use your tongue to rub it all over the soft tissues of your mouth. You may have to do this at least once in the middle of the night as well. If you have no problems breathing through your nose, you can do what I did which is use an elastic headstrap to keep your mouth colsed until you can train yourself to do this without it. While they make one of these that is commonly used in apnea patients that have a cpap machine, I found that my wife's head sweat band from playing tennis worked very well. Under my chin and over the top of my head.