Greetings Shake hands and say buongiorno (good morning) or buonasera (good afternoon/evening). If you know someone well, kissing both cheeks (starting with their left) is standard.
Polite language Say mi scusi to attract attention or to say 'I'm sorry', grazie (mille) to say 'thank you (very much)', per favore to say 'please', prego to say 'you're welcome' or 'please, after you', and permesso if you need to push past someone in a crowd.
Cafes Don't linger at the bar; drink your espresso and go.
Body language Be wary of making a circle with two hands (which in Italy means 'I'll kick your arse'), an A-OK signal ('You might be gay') or the devil horns with your hand ('Your wife is cheating on you').
In churches Never intrude on a mass or service.
Selfie sticks Officially banned in Florentine museums. Elsewhere don't stick them in front of other people's faces or those trying to view world-class art in relative peace.