Try making it a habit(Cue, Routine, Reward). After 3 decades on earth, I finally feel like I have a decent sleeping habit. Two things that worked for me, having a consistent schedule and creating a cue/trigger associated with sleep.

I started wearing ear plugs and facemask to sleep. I started wearing it because my partner usually sleeps much later than me. First couple night took some adjusting, but after a week or two. I realized something. I started falling asleep almost immediately after putting on the ear plugs and facemask. That's when I made the realization I unintentionally created a habit with the ear plugs and facemask as the cue.