How do I fix my sleep schedule

[Aeronaut]

so due to certain circumstances, I've been staying up later and later the last few weeks; the last couple of days, it's been exactly the opposite of a normal person's sleep schedule. I wake up around 7PM, and go to bed around 9AM.

It's really bizarre, because I never know what day it is or really have any sort of body-clock. I've been telling myself it's fine, because my classes will be over in ~3 weeks, and then it's summer and it doesn't really matter (this isn't entirely true, but it will effect my life less).

But yea, I missed an exam today, because I just could not physically fix my schedule. Fortunately, my professor is awesome and let me postpone, but i'd really not like anything like that to happen again.

Does anyone have tips/tricks for fixing a botched sleep schedule?

[Aeronaut]

My fix-it solution for now is to drink a 5 hour energy today, and then hopefully tonight when I'm inebriated, i'll be able to get to sleep a bit better.

Yes I know, I treat my body right!

[Aeronaut]

But thanks for the advice, everyone! This is a habitual problem of mine, so all of this really helps