This be for dreamers who are interested. The key to the doorway of lucidity can be a dream sign. For myself, that dream sign without a doubt is to fly up in the air. I take a running start and then leap in the air, sort of like sliding into second base but without falling. I've done this so many times that it always works. I just leap up in the air and off I go. There can be doubt that I am dreaming. So this is what it takes for me to become lucid.