There are a lot of drunks in Germany, and there are a lot of really creepy Turkish old men who just like to talk to any girl that they can find. Know what it sounds like when someone's flirting with you in German. That's all I can say. And it's okay to just not talk to somebody.
Parking is such a hassle in Germany. It depends on where you live though. If you live pretty rural, then you're going to be fine. But even in like not very large towns, it's just Germany is such an old place. And so the cities are built for walking, they're not built for cars like they are in the states. And so the streets are all super narrow and so it's always parallel parking and the spots are sometimes really, really narrow. And so I would recommend practicing your parallel parking. Getting really good at that because you will need it if you ever drive in Germany.
A lot of people will know that you're not German, and so they might mistake you for an unsuspecting tourist or that you have no idea what's going on, which you're not, usually. So if anyone says, hey, come down this alley, I want to show you something. Don't follow them. That happened to me making a painting, they're like, hey, come down here, we want to show you something. I'm like, ah, no, we're going to go and just made our way towards a populated place as soon as possible. Probably avoid people, I don't want to say you should, there are some people you should generally avoid, like, try to stay away from the violent drunks as much as possible.
In Germany it is very common to follow the rules. So I would say one thing you should do is follow the pedestrian rules with crossing the street. So there'll be a little light just like basically in America and it will be green when it tells you to cross the street. So I would say wait for that and don't cross the street like at random places because it's against the law first of all and second of all super embarrassing when they just see you walk in a place you're not supposed to.