What cultural faux pas should I try to avoid making in Bonn?

"In Bonn, punctuality is highly valued, so avoid being late for appointments or meetings. It's also considered rude to interrupt someone while they're speaking, so wait for your turn to talk. When dining out, don't start eating until everyone has their food and the host has begun eating. Avoid discussing World War II or the Holocaust unless it's brought up by someone else, as these are sensitive topics. Also, refrain from making Nazi jokes or gestures, as they are illegal and highly offensive. In public places, keep your voice down to avoid disturbing others. Germans value their personal space, so avoid standing too close to someone or touching them unless you know them well. When using public transportation, don't put your feet on the seats and give up your seat for the elderly or pregnant women. It's also important to remember that in Germany, it's customary to greet people with a firm handshake. Avoid using the informal "du" to address someone unless you're invited to do so. Instead, use the formal "Sie". Lastly, don't litter. Germans take great pride in their clean cities and littering is frowned upon," remarked another expat in Bonn, Germany.