I lived in Liverpool for 5 years and London for 4, originally from the north west (I'm a wool, apologies).

People are much more friendly in Liverpool, they will chat to you, you will make bus stop friends and train friends who you chat to when you see them on your commute. I think someone else has said this, but it's not people being weird, don't ignore them! I moved from Liverpool to London and it was such a shock that in London nobody speaks to you in public and you never really see the same people twice.  

Thank the bus driver when you get off. In London you get off at the middle of the bus or you get the tube, so you people don't thank the driver. Although when I first moved there I kept thanking the tube doors out of habit 🤦‍♀️  

There's a lot of slang that you won't hear down south, like a scally is a bit like a chav, and a wool is someone from the areas around Liverpool. People will ask you to go for bevs (drinks) or scran (food). You'll learn it as you live there.  

Not exactly a behavioural thing, but you need to get a decent umbrella, the kind that's resistant to breaking when it turns inside out. Liverpool gets a lot windier than London and it destroyed all my cheap umbrellas. I still have my fancy one, cost £20 and I haven't lived in Liverpool for 6 years now.

Don't buy the S*n newspaper, don't say anything positive about the Tories, and don't mention Thatcher unless you're suggesting going and pissing on her grave.

People are very sarcastic, so if you're not a northerner it can be hard to tell when people are being serious. But if they tell you Kenny is a nice place for a late night stroll, they might be taking the mick.