No one else appears to be answering this, so I will just tell you what I do. First drill a tiny hole in the flat part of the thermostat as that will help in the long run. Second, button up everthing except the radiator cap and fill it until no more fluid will go in. In a couple of minutes some of the air will come out by itself. After that, grab the upper radiator hose and squeeze it to purge the air in the upper system. Refill to the limit again and repeat. Eventually no more air will come out. This gets most of the air, and by squeezing the radiator hose you will have purged much of it from the upper part of the system.