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

"In Milan, the most important thing to remember is to be respectful and polite. It is important to greet people warmly upon meeting them and show them respect; avoid offensive language, rude or brusque behaviour, and interrupting others. In spite of the modern, fast-paced atmosphere of Milan, it is important to be aware of and adhere to the city's strict dress code. Milanese tend to dress more formally than elsewhere in Italy so it is best to opt for conservative clothing when out in public. Also, when visiting churches, it is important to dress appropriately, regardless of gender and to observe any signage indicating different dress codes. Lastly, do not be offended if Italians stick to their own cliques, as it is usually seen as a form of politeness and respect to their own. While engaging in conversations with Milanese, avoid talking too loud as it is seen as an impolite gesture," said another expat in Milan, Italy.