In terms of what you need to bring, essentially just yourself but perhaps a bag to carry snacks and a water bottle that can be refilled at any of the numerous water fountains in the city. You may wish to bring a camera or smartphone to take photos where permitted. Please note it is also required by law to carry ID in Italy – a photocopy of your passport, ID card or driving licence will suffice. Also, cash is king in Italy – it’s always a good idea to carry a little just in case.