Circadian code talks about why your sleep is so important. Highly recommend that one.

unfortunately, I'm a morning person that doesn't have a social life and caffeine and screens literally don't affect my sleep

so nothing directly helped me per se (but I would say I'm an outlier)

the thing that helped me keep a regular bed and wake up time was the fact that I wanted to play games in the morning before work - which I have now changed to going to the gym instead.

So, for me, I just decided what time I really wanted to get up and started getting up then. I do make sure my alarm is on my desk so I literally have to get out of my bed to turn it off so that helps. Once you're out of bed, put on clothes and just sitting down helps to wake you up.

Others say drinking a glass of water, going straight into a shower, or even a jaunt to another room has also helped.

So yeah, I think I've heard these things from the copious amount of time I've spent on reddit -.-