To the great suggestions above, I'll add:

A dairy product soon before bed helps me sleep, particularly a yogurt. This is a semi-known thing.

Darkness in the room. I really need this for good sleep.

The most comfy bedding, pillow, and nightwear possible.

A sound machine is extremely helpful. I do best with the soundmachine sounds over music or definitely not TV.

Consistent bedtime. Bodies and minds like routine.