If I stayed up for a day, what time should I go to bed to wake up at 7:00 a.m and not be tired?

So I stayed up for a day because I'm resetting my sleeping schedule for school. But I don't know what time to go to sleep. I usually fall asleep around 8 p.m if I stay up. But I wake up at like 4, I don't understand. I'm so exhausted when I stay up and shouldn't that make me sleep longer? Even when I don't stay up I sleep like 12 hours on a weekend.