Italian dress code...
No matter how hot it is, taking off your shirt is not cool. Chicks are dressed to the nines pretty much always. They wont leave the house without getting dolled up (in Rome).
Men wear shirts and just open more buttons as needed (the top 3 are rarely buttoned). And most italian men wear pants. Rarely do you see an italian man wearing shorts.
Men my age (25-35) usually wear an untucked collared shirt and nice jeans or pants with nice shoes.
I pretty much always wore flip flops, a collared (long sleeve, but cuffs folded back 1-2-3x) shirt and jeans.
If you don't want to look like a tourist, men your age (35-45ish
) usually wear the same, but will tuck in the shirt.
Anything you'd wear on a golf course in Calgary screams tourist in Rome.
Nice jeans, button up shirt and decent shoes will help you blend in and likely reduce any tourist rage your italian server may have that day.
Churches demand covered knees and shoulders. And no beer. Gotta leave that at the door.
Chicks dressed like sluts will not get in by batting their eyes. This is not a cop with a radar gun, this is a priest.
It does get very hot in Rome, and it may sound stupid that they wear so much clothes, but you'll discover that the italians have perfected the art of walking in the shade and strolling very leisurely so as not to break a sweat.
Oh, and siesta. Siesta is usually from 12/1 - 2/3/4. It varys. And try not to go for lunch between 1&2. Thats when italians are eating and you'll be relegated to the 'back of the bus' until they are all finished.