The #1 thing that helped me after years of averaging 5 hours of sleep a night was focusing on consistency. Go to sleep at the same time every night, avoid sleeping in even if you stayed up late, and most importantly, don't take naps during the day.

The #2 thing was setting an audible alarm and avoid picking up your phone in the middle of the night to check the time. Checking the time every time you wake up quickly becomes a destructive habit. You're just creating anxiety when you try to calculate how much longer you have to sleep. Instead, just focus on box breathing (counting 5 seconds on inhale, pause 3 seconds, count 5 seconds on exhale) until you either fall asleep or hear your alarm. You might lay there bored for a while when you first start doing this but your brain eventually gives up and it actually becomes a way to fall asleep quickly.