Perhaps a strange tip, but I was surprised to come across this public toilet, which You have to insert a 1 euro coin into a slot, before You can be admitted through a gate into the toilets.
I was also surprised (but pleased) to see that it was open, despite the islands attractions being closed on Christmas Day
The toilets were very clean, and there was plenty of hot water and soap, but it was quite expensive. There was an attendant, but she didn't acknowledge my presence at all, which felt a bit strange, as I doubt if many visitors had passed through that day.
I did check that she was breathing before leaving!
Near the museum, follow the sign
I am amazed I am the first person to have Torcello page. So I am going to say Torcello itself seem to be off the Venitian beaten track. It really is worth a visit and its so easy to get to.
On the Island itself, Its very small anyway, so you can not wander off too far.