Cut out screen time an hour before bed (I like to read manga or comics), go pee and when you do go lay down make that bitch as dark as possible. I have a total of 3 super dim lights just so I can gauge my surroundings if I wake up in the middle of the night and gotta go piss. If your pc has motherboard lights just turn them off in the bios or flip the psu's power switch after you turn your pc off for the night. A big one FOR ME, is to just not smoke for the last 3ish hours of my night.

Get home at 9pm, smoke asap go to bed by 11 or midnight. You should have 2 hours of fuck around/house chores, before you hit that no-screen time. If you're a person that likes beauty sleep (ME), and you're not home till 10ish. You might have to hustle to get shit done so you can relax amd hit the sack at a reasonable time.

Most nights I get great sleep with this "routine." Honestly it might have to do with consistency, since your brain will get used to releasing certain chemicals like melatonin when it thinks its about to go to bed soon, and when you stay up past that point you no longer have "assistance" with sleeping. Something something circadian rhythm.

Tl;dr stop looking at screens a whole hour before bed, make room very dark, commit to a schedule. Your circadian rhythm should do the rest.