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

"In Bilbao, Spain, it is considered rude to interrupt someone while they are speaking. Always wait for your turn to speak. Avoid discussing sensitive topics such as politics, religion, and the Basque separatist movement unless you are very familiar with the person you are talking to. Do not assume everyone speaks English. While many people in Bilbao do speak English, it is respectful to learn a few basic phrases in Spanish or Basque. Avoid comparing Bilbao to other Spanish cities. The Basque region has a distinct culture and identity, and locals may not appreciate such comparisons. Do not be overly punctual for social events. It is common in Spain to arrive 15-30 minutes late for social gatherings. Avoid wearing beachwear or overly casual clothing in the city. Bilbao is a stylish city and locals tend to dress smartly. Do not expect shops and businesses to be open all day. Many businesses close for a few hours in the afternoon for siesta. Avoid leaving a large tip. In Spain, it is customary to leave small change or round up to the nearest euro, but large tips are not expected. Do not rush your meals. In Spain, meals are a time to relax and enjoy the company of others. Avoid calling someone by their first name unless invited to do so. Use formal titles like "Señor" or "Señora" until a more informal relationship is established. Do not refuse an offer of food or drink. It is considered polite to accept, even if you only take a small amount. Avoid being loud or boisterous in public places. Spaniards value respect for others and public spaces," said another expat in Bilbao , Spain.