[mft_]

> The biggest factor is - has my brain settled. Background and noise don’t matter.

I'm there too on this. Something I've found helps is listening to certain types of audio. Some audio books can work, but if they're too engaging or interesting it's counter-productive.

My current solution for this is a particular YouTuber; I noticed a long time ago that watching his videos in bed (when I already given up on trying to sleep immediately because my brain was too alert) seemed to help me relax and feel drowsy. Now it's almost a switch - start a video, phone face down, and I rarely need a second one.