We are talking about congested traffic, mostly slow-moving, in narrow roads and streets. Textbook rules regulating priority make no sense, as nobody would get past intersections from a low-priority road. The key is to be VERY attentive to others’ reactions and be assertive.

Thus, when there is a little gap, push in, and the next car will slow or stop (as long as it is not a luxury car, truck or bus, but they will then hit their horn to warn about this intention) just enough to let you in. When turning left, just push into the first direction (yes, stopping it) and wait until there is a similar gap from the other direction and repeat. It works, just observe others doing it first. Don’t worry about cars other than in the direct vicinity tooting horns: this is just a way to ease frustration about stopped traffic.

Similarly for pedestrians, cars will let you through anywhere, not only on marked crossing, if you observe a few rules: don’t step out in front of large or expensive vehicles and within braking distance, be very obvious and steady in your behaviour (step off the kerb and keep going). Again, traffic will slow just enough to let you through.

Faster roads are a bit more disconcerting, as the pushing in happens much more quickly and people don’t use indicators, but the principle is the same.

Old towns require special attention, as the roads are narrow and often there is no footpath. Thus, it is impossible to see crossing traffic until one’s car is a third of the way into the intersection. Thus, if crossing drivers see a car nose appearing, they hit the horn to tell the driver to stop: logical if you think about it. If you are far enough in to block their way, other cars will stop without rancour.

When mastering the local rules, you will in fact find Sicilian drivers quite courteous. From memory, similar rules are applied in other parts of Italy too, especially in the south.