Last year I went to Venice with my 2 friends from France, when we found unbelievably cheap bus ticket from Milan to Venice, thanks to Flixbus.
We reached Venice in Tronchetto bus stop at 12:30 in the afternoon. Tronchetto is in the Island of Venice and from there you can take ‘People Mover’ (electronic train) to Piazzale Roma, or even walk there. From Piazzale Roma you can start to walk in the narrow streets and alleys of Venice with bridges over the canals and start to explore the magical world of Venice.
But the best and cheapest way is to travel by Vaporetto or water-bus, which is the most used public transport of Venice. We bought 20 euro ticket for 24 hours. It is a very good deal because with the 24-hours Vaporetto pass you can travel not only in the canals of Venice bus also you can go to other beautiful islands near Venice like Murano, Burano, Mazzorbo, Lido (beach) etc. I’ll talk about all these islands soon. Here is the routes in which Vaporetto travels, www.actv.it/en/movinginvenice/waterbusservicetimetable