The main reason why you loose a lot of sleep quality is because you sabotage yourself with the believe that you can’t stop thinking and can’t control it. It’s most of the time not even a conscious proces. Its an automatism caused by not knowing better. Here is the solution: it is true that you can’t stop thinking, but you can think (be) in a kind of no man’s land. Call it the zero zone. All thoughts that coming in (stiumulus) travel to the part where you pay attention to them. That is the ‘talking’, ‘thinking’. So imagine that in that travel to the zone in your brain where you start doing something with it, there is an empty zone, call it the zero zone, in which you also can decide to focus on that, and not doing something with the thought.
Victor Frankl, called it a space between the stimulus and response (what you do with whats coming in: feelings, thoughts). When you want to sleep and you realize that you have a choice whether to do something with the stimulus or not doing, and keep your attention in the empty space (the zero zone); it’s the answer to sleep and giving up on it.
In the ZEN Sleep technique it’s step one: choose to sleep and stay in the Zero Zone.