I guess it depends on your university.
I attend the University of Sheffield, and when I got here, my dad and myself went and got my keys and signed for some insurance, were given welcome packs, and settled in. I set out all of my stuff, met my flatmates and then my parents (mid-way through divorce and hating eachother!) went to get me some freezer food for the week. They got lost, so I was in my flat alone (it was 8am and my other flatmate who arrived then went to get food too), so I decided to clean the shower and dye my hair. (':
Long story short, they got back eventually, and I had to blow dry my hair etc, so when my new flatmates arrived, I was just in my room trying to put my stuff away (my room is a double bedroom, so I had a lot of stuff to sort out!).
My flatmates thought I was weird and antisocial apparently. (':
I later went and sat on the bed of the first flatmate I met and we discussed the meetings we had in the week (meeting personal tutors, introductions to the course etc.)
That was it really.
Although they do all differ. Any questions that I've failed to include, please ask.
Congratulations and good luck! x