Most of the main attractions in Venice can be reached by foot or water taxi. However, if you're short on time, consider taking the vaporetto (water bus) to get from one side of the city to the other. A single ride costs around $7 and takes approximately 30 minutes.
If you have more time, consider adding a visit to the Doge's Palace or the Basilica di San Marco. If you have less time, skip the Peggy Guggenheim Collection and spend more time exploring the beautiful streets and canals of Venice. Don't forget to wear comfortable shoes and bring a water bottle, as Venice can get quite hot and crowded during peak season.