Sicily

Take a flight either to Palermo, Trapani, Catania, or Comiso. It's cheaper (if you buy early) and much faster. If you take the train, that train will go via ferry on the strait of Messina. Sounds like fun, but I would skip it personally.

I took the night train from Rome to Catania in 2015. Do not make the same mistake! I guess the rails aren't as smooth as they need to be for a passenger train. There was a constant side-to-side jerking that kept me awake all night long. It was an utterly miserable experience, as was the following day since I'd had no sleep

There are ferries from the mainland (Google should turn up some links), but I'd fly.

Where on the mainland? The ferry crossing from Villa San Giovanni is about 30 minutes. The train from Roma Termini is about nine hours.

Fly if u can and if Palermo or Catania are your destination areas.

We took the Sicily tour just this March (and we loved it). We flew AirItalia from Rome to Palermo On the way back, we flew AirItalia from Catania back to Rome. AirItalia was inexpensive, but they were a little late in both directions, plus if they think your suitcase is too large to carry on, they will charge you to check it in (unless you bought a more expensive ticket)

I did take the train from Catania to Rome after the Rick steves tour. I was in no big hurry to get to Rome and enjoyed the trip though it is 9 hours. There is no food car on the train so I brought my own. You can also get food when they load the train on the ferry and can get out and walk around and see the crossing. I kinda agree I wouldn't take a night train but day time was just fine. Got to Rome and my hitel in time for dinner.

I agree, fly. I flew to/from Sicily in February. It was under $100 each way, and that was for the middle class of ticket with higher luggage allowance and seat selection. The hand baggage only ticket would have been closer to $50 per ticket. The airline you use may vary depending on from where on the mainland you fly.

If you're in very southern Italy, then train might be a good option. There may also be an overnight ferry option from Naples to Palermo.