1. It is perfectly reasonable to come in to a dorm at 1am and switch on the light, even if 5 people are already asleep in the dorm. This is because if you are awake at 1am and they are asleep, you are a much cooler person than they are. This rule is doubly true if you are only switching on the light to put on more make-up/change clothing/grab extra jewellry before heading out again. Then you are really, really cool and are further, allowed to make a lot of noise as said clothes, make-up etc. are retrieved from various parts of your bag.
2. If you are reading in the dorm room with the lights on, it is perfectly unreasonable for someone to ask you switch them off so they can go to sleep, even if there are innumerable common spaces within the hostel (with lights) were you could also read and nowhere else they could sleep. This is thanks to the ‘I-was-here-first’ clause.
3. You should generally be Australian. And you should have loud conversations about how awesome Australians are whilst standing in the dorm room, making any other nationalities in the room feel uncomfortable and left out. If other Australians are in the dorm room and not participating in said conversation, they are too be ignored and/or sneered at.