Living with someone is never easy. Whether you’re partners, friends, or random students who met by pure chance and equal need to share a flat, the truth is, a big part of the deal comes down to not-so-sweet moments. Like, noticing your biscuit bag rapidly shrinking in size, or drinking the chamomile tea and shoving in the ear plugs since your roommate is a night owl with a passion for techno.

Sometimes, though, it gets more awful than that. And when you realize your relationship has become somewhat passive-aggressive and your sticky note battle is getting out of hand, it may be too late to save your (and your roommate's, for that matter) sanity.

Fortunately, there are some things everyone can do to make sure sharing a flat is not a one-way ride to hell. First, make sure you’re compatible from the very beginning. I know, nobody is going to marry their roommate, but being sure you have similar lifestyles, hobbies, and at least, are not immediately averse to one another is a good start.

However, many people who have experienced a flat share can assure you that living with your best friend is not a good idea either. Even though it sounds like a dream come true, living with your BFF may reveal less savory aspects of people’s personalities (And personal hygiene.) After all, it’s not worth putting your friendship on trial just so you two can spend even more time under one roof.

The truth is, when you start living with someone you know, little things that you were not particularly keen on about their personalities often snowball into giant arguments.

Even though there are no existing rules governing how roommates should live with one another, psychologist Fredric Neuman suggests a couple of things to have in mind. First, it’s mutual respect. “By respect, I mean certain specific things: Do not eat the other person’s food unless you ask first. Do not borrow clothes, or pick up money lying around, or take up any other possession of the other person without asking first.”

Second, it’s following through financial commitments so that none of the roommates feel pressured. Also, chores should be done without reminding one another, so make sure to set up a schedule in the communal zone.

According to Fredric Neuman, it’s best not to keep close track of everything you do for your roommate. “Weighing every action on a scale leads invariably to someone feeling disadvantaged,” he argues, so it’s best not to set your expectations too high.

This should be common sense, but you’d be surprised how many roommates actually don't comply with not going into your roommate’s bedroom unless they are present. Setting boundaries before starting to live together is a great way to make sure everyone is one the same page.

For some people, common sense may vary, and letting everyone know you’re not comfortable with anyone visiting your room without you present is a simple way to avoid miscommunication.