Italian queuing is different from British/German/Japanese queuing. There is often no visible line. Instead, there’s a cluster of people who each know their position through a social contract you don’t understand yet.
Plan your trip →Delis/bakeries/pharmacies: take a number (numerino) from the dispenser. Wait for your number on the screen. If there’s no number system: when you arrive, ask "Chi è l’ultimo?" ("Who’s last?"). That person acknowledges you. You are now after them. You can wander away, check your phone, browse — as long as you know who you’re after. Post offices/banks: always a number system. Bars: at a busy bar, there’s no line. Approach the counter, make eye contact with the barista, and wait. They know who was there first (usually). Don’t wave money or snap fingers.
Cutting in line (saltare la fila) happens and is met with loud protests. If someone cuts, speak up: "Scusi, c’ero prima io" ("Excuse me, I was here first"). Italians will support you vocally. Skip-the-line tickets at museums are worth every cent — the Uffizi/Vatican queue can be 2+ hours in summer.