This technique is based on a very simple mechanism: the Body-Mind association. NLP (Neuro-Linguistic Programming) has put well-known natural processes into words, creating anchors that your mind associates with one or more stimuli such as a smell, gesture, or even music.
You will create one of these anchors to access it on demand whenever you want to fall asleep more quickly.
This technique takes around 10 minutes. Make sure you have enough time before you start.
It's best to use this technique in your bed, or anywhere you can lie down.