Obvious second is avoiding caffeine anytime after lunch.
Third, set an alarm on your phone for 30 minutes before you’d ideally like to be sleeping. When the alarm goes off, get ready for bed and then get into bed.
To get to sleep (tricks someone showed me in uni): turn off all lights so your room is pitch dark. Keep your eyes open as long as you can, even after they feel droopy. ‘Look’ into the darkness. Try to create an Elaborate story in your head with characters and settings. Build gradually on this story night after night. Each niggt you only need to work out a tiny additional detail, like what characters wear or say or do. The story builds slowly and gradually and you’ll start to trigger your brain to get tired through just thinking of the story.
Before long you’ll hopefully be sleeping at your target time.