From the airport, you can take a bus or taxi to Piazzale Roma, which is the end of the line for land vehicles in Venice. From here take the Vaporetto (Line 1 or 2) to the San Marco Vallaresso Terminal. Your hotel is a short walk from here. I would suggest getting walking directions from your hotel as it is very easy to get lost in Venice.
Another option is to take the Alilaguna water service directly from the airport. This service eliminates the transfer at Piazzale Roma. It’s a longer boat ride that crosses the lagoon, but it can be an interesting approach to Venice if the weather is nice. The Alilaguna Orange Line goes down the Grand Canal before stopping at the San Marco Terminal, which is a nice introduction to Venice.