English speakers aren’t habituated to an informal “you” and a formal “you.”
It just doesn’t exist for us. We use “you” for our best buds and “you” and for addressing a stranger. When speaking Italian, there is “tu” (second-person familiar) for family and good friends, and “Lei” (third-person formal) for strangers and elders. (“Lei” can be confusing because it also can mean “she.” This is distinguished in writing by capitalizing the L, even when used mid-sentence.)
Despite the affectionate and buoyant nature of many Italians, they’re taught from an early age the importance of respect. They are cautioned by their parents against getting too close to people too quickly. Trust and familiarity must be earned. And when you earn that trust by building up to familiarity, your Italian experience will be much richer.
When speaking with strangers, default to the “Lei” (third person formal).
This structure can be found in French and Spanish as well and isn’t some strange convention put there without good reason. This is an integral part of romance languages and their associated cultures. I highly advise not skipping past learning when and how to be formal and and when and how to be familiar.
“Ciao!” just might be the biggest offender.
I can say this because I used ciao like water during my first years living in Italy. “Ciao!” can mean both “Hi!” and “Bye!”, it’s quick and easy, right? But, do you want to be told (like I was), well after the fact, that over-familiar salutations can be considered “maleducato” (rude/uneducated). Ouch!
Also, you will want to avoid using second-person-familiar verb tenses with strangers, elders, and officials. No, it won’t end the world, but you may unintentionally end up offending someone and making them be wary of you. You don’t want that when you’re working to integrate yourself into the culture (and work through the bureaucracy).
So, what DO you say if you’re uncertain?
I encourage you to check out a previous post to bone up on the Italian art of salutations and goodbyes. The never-fail greeting is “Salve, buongiorno.” (“Hello, good day.”) Or ,“Salve, buonasera.” (Hello, good evening.)
For saying, “Goodbye,” try “Buona giornata” and add “Arrivederci.” (Have a nice day. Goodbye.)
Wait for the other person to invite you to use “tu.”
This can happen in a couple of ways. The first is when the other person begins using “Ciao!” with you or by using the familiar (tu) verb tense. That’s your signal, your invitation to do likewise. The second way is when the other person basically says one of the following:
“Possiamo darci del tu, se vuoi.” (We can give each other (ourselves) the tu (you inf.) if you want.)
“Dammi pure del tu.” (Go ahead and give me the tu.)
Still, there will be Italians who don’t set a proper example.
Don’t follow them. As I said earlier, there are places like Rome where Italians speak with greater familiarity to strangers. They’re giving you the permission to use ciao and the familiar verb tense. So, go ahead and respond in kind if you want. BUT I don’t recommend copying them when you meet strangers, and don’t make it your standard practice when speaking Italian. For instance, the speaking style in Milan is more proper, and over-familiarity might not go over so well.