Elon Musk has some rather simple advice for improving the quality of your sleep, with a simple tweet: "For improved quality of sleep, raise head of your bed by about 3" or 5cm and don't eat 3 hours before bedtime". That's all.
MrBeast replied, tweeting "anyone want to explain why these two things help to me" to which Musk replied: "Good chance you're experiencing at least mild acid reflux at night, affecting quality sleep without consciousness awareness". MrBeast replied again, saying "ah, interesting. I currently sleep 9 hours a night and I've been trying to get it down without reducing my energy levels/brain function so maybe this will help".
As someone who also strives for good sleep, I invested over the years into an adjustable bed with a really awesome mattress, and some high-quality pillows and quilt. Hell, I've even got a weighted blanket -- which I absolutely love on some nights, and even my two daughters love weighted blankets -- which helps the quality of your sleep.
I do agree with Elon, raising your head helps -- I get laughed at by my partner because I have my head up higher on either a thicker pillow, or an additional pillow, I can't do thin pillows -- it really does. I used to travel overseas non-stop before the pandemic, so I spent many, many nights in hotels... multiple pillows, quilts, good sleep is my life.
It's actually cool to see Musk casually tweeting out about improving your sleep, which every single human being on the planet does, and it's important -- you spend about 1/3 of your life laying on your bed.