A guide to

How to be:
Less gross: It's alright to use your room mate's high-end conditioner once in a while, but using their razor, even in the most dire of circumstances, is never okay.
Nicer: Don't be that guy at the laundromat that removes peoples' clothing within 3 minutes of it being done. Save those awkward moments when they walk back in the place and see you holding their 4-year-old panties, and just wait your turn.
Better than your ex's: If you feel like dressing up and celebrating- do it! You don't need to finish grad school or get engaged to party!