3. Have a firm handshake
If in your first contact with her dad your hand feels like a weird limp fish, he will never talk to you again. And if I were her mom I wouldn’t either.
4. Go to the bathroom as soon as her mother brings up marriage and kids
Every time. If you haven’t made plans with your girlfriend on these subjects, then it’s none of her mom’s damn business. So instead of saying exactly that, excuse yourself and go pee.
5. Avoid politics
Even if your views basically align, something her parents say will piss you off, and vice versa.
6. Avoid making friends with her weird uncle
Even though he REALLY wants to make friends with you. There’s a reason no one talks to him.
7. Don't give her cousins their first beer, even though they think you’re super cool
I mean, you ARE super cool, but let them figure out booze on their own.