Deepen your breath while you notice and recognize sensations in your body and mind. Deep breathing increases oxygen flow to the brain, stimulating the parasympathetic nervous system which calms and relaxes the entire body and mind.
Embark on a meditative journey to sleep. Learn how to relax and place aside outside worries.
Read the science:
https://blog.caravanwellness.com/sleep-is-for-the-strong/