Note that Italy uses (mostly) international road signs; you can find a glossary of them at the bottom of the MVRO page.
Italian signs generally don't indicate cardinal direction (N/S/E/W) or road (SS 7, etc.), but rather which major towns they lead to. Thus, it is useful to know roughly what towns are in what direction. For example, Roma (Rome) is north of Naples, so if you want to go north, follow the signs for Roma. Roadgap explains Italian signage in more detail.
See the driving in Naples page for tips on driving in Naples specifically
If you are buying a car in Italy, this may be your first time driving a manual transmission car (it was for me!). Some resources to help you learn how to drive a "stick shift":
Italians are known as "crazy" drivers, and Naples is infamous for having the "worst" drivers in Italy! However, this is because they simply follow different rules than Americans. Or, more precisely, they only follow one rule:The First (And Only) Rule of Italian Driving: Do not hit anything that is in front of you.
The movie Gumball has another take on the First Rule (see clip on the right).
For other points of view, see Joe Casale's thoughts on driving in Italy, Luke Swartz's blog post listing different driving signals, Italy Beyond the Obvious' 10 Habits of Italian Driving, and Bruno Bozetto's hilarious animated short, Europe and Italy.
"I love the way Italians park. You turn any street corner in Rome and it looks as if you've just missed a parking competition for blind people...Romans park their cars the way I would if I had just spilled a beaker of hydrochloric acid on my lap." - Bill Bryson, Neither Here Nor There
"If there is an Italian in front of you and an Italian in back of you, you're OK." In other words, even if there is a big "no parking" sign, if there are Italians parked along that road, you probably won't get ticketed or towed. However, if there is no one parked on a road, and there isn't a good reason (e.g. it's August so nobody is in town), then even if there isn't a "no parking" sign, beware parking there!
Sometimes, when one parks in Naples (or elsewhere in Italy), someone will offer to "look after" your car, by approaching you with an oustretched hand and asking "Prego?". Thus, at least one American calls such an unlicensed attendant "The Prego Man". Some people choose to ignore the Prego Man, and some choose to pay him (it's almost always a "him")...just be forewarned that sometimes if you don't pay, your car may not be in great shape when you arrive back.
Darin Riggs Parking Rule
Should you have a problem on the freeway, try to pull over in one of the shoulder spots marked "SOS." Few Italian freeways have large shoulders. Also, keep a reflective triangle and vest in your car so that oncoming drivers will see you. If you need to explain what is broken, check out Car Words in Italian. The Automobile Club of Italy (ACI) is the equivalent of AAA in the States—among other services, they provide a towing service throughout the country. They have various annual memberships that give you various services.
For autoparts Autozone will ship anything free to an FPO address.
Most major Italian highways—including the frequently-used Tangenziale (or "Tange") that cuts across Naples—are toll roads. For example, the Tang costs €1.00 each way (regardless of how far you drive on it).
3 ways to pay (in increasing order of convenience):
Also: do not leave your Telepass in your car when you park it! Even though it is a stupid thing to steal (since it is easily tracked/deactivated), some people have had their car windows smashed to grab the Telepass.