A few roommate rules:
1) Lower your expectations
Don't expect roommates to do or be anything like you, and in fact, expect them to be sloppy, inconsiderate, and generally lame. They probably will be at some point, some worse than others, of course.
2) Write out the house rules
Along with #1, get rid of any possible misunderstandings or assumptions by writing out the house rules. Make a rule about when bills are expected to be paid, (yes, your roommates will "forget" to pay you), make a rule about what's expected to be cleaned up (yes, your roommates will expect "someone" to clean the house), make a rule about house guests (eventually a roommate will think it's perfectly fine for his/her girlfriend/boyfriend to be at the house 24 hours a day, 7 days a week, effectively giving you another roommate who doesn't pay any bills.) Write it all out. Later on when there's any kind of issue, you can always point to the Da Rules and go, "Hey dude, you knew the agenda coming in, it shouldn't come as a shock that we dont want your girlfriend living here too."
3) Fuck democracy
When it comes to roommates, democracies don't work. Get deposits from everyone involved and put the bills and the lease in one person's name. This way if/when one roommate turns out to be a deadbeat, or an inconsiderate prick, or a general loser, there's no great problem getting rid of them. Putting other people on the lease or having bills in their name only causes problems and power struggles. Democracy doesn't work. To cover the risk of having it all in one person's name, just make sure deposits are collected beforehand.
4) Square things with the landlord
Make sure the landlord knows you're the head of the household and that other people will be living there in a roommate situation. If the landlord is cool, get him to sign a paper stating that he authorizes you as the primary leaseholder to sublet or evict people at your discretion. This way if there's a problem in the future, you won't need to involve him and you can handle it all on your own with police, eviction court, etc.