Do try to stay for as long as possible, even months or years. Apart from the obvious draws, Venice is a great base from which to set off on trips around the lagoon, to the beach (Lido, but also Punta Sabbioni and Jesolo) and to picturesque local towns like Bassano del Grappa and Vicenza.
Do visit the museums and churches, often a sanctuary from the crowded alleys. The secret tour of the Doge’s Palace is essential, and some guides can organise a visit to St Mark’s Basilica at night, when it’s empty and dramatically lit. Special arrangements can also be made to look around the Arsenale (once the heart of Venice’s naval power) and the Fondazione Cini (on the island of San Giorgio) which, through their architecture, views and particular contexts speak more than words about Venice.
Don't walk around with your nose buried in a map or worry about getting lost. It won’t be long before you find a familiar landmark, or a sign to Piazza San Marco, Rialto or Accademia. The areas of northern Cannaregio, lower Castello and Giudecca are particularly fine wandering spots.
Don't eat anywhere with a plasticated menu showing photos of the food on offer. Or give business to the absurd drinks and snack vending machines that have recently landed around Venice. The only good one is the milk machine parked in the Garage Comunale, Piazzale Roma—it dispenses fresh, unpasteurised milk straight from the nearest dairy.
Do try some Venetian specialities when eating in or out: castraure (earliest artichokes, fried or stewed), mauve mantis shrimp, and moeche—little soft-shell crabs from the lagoon—are all delicious, as is the wild duck with artichokes at the Antica Trattoria alla Maddalena, just by the vaporetto stop on the outlying island of Mazzorbo.
Don't come on a cruise ship: they are ugly, spoil the view, damage air quality and building fabric, and destroy the fragile lagoon ecosystem.
Do rent a bicycle and explore the Lido or the little-visited area of Forte Marghera. Take a picnic bought from the Rialto market or the vegetable barge on the San Barnaba canal.
Do take a gondola ride, but don’t let your gondoliere talk on his mobile. Nor should your taxi driver go too fast across the lagoon, or too near small boats or other islands: the wake waves are damaging and dangerous.
Don't bother with shops selling mass-produced tat (mainly Chinese). This applies to clothes and handbags as much as rip-off “Venetian souvenirs” in the form of tacky masks and glass geegaws—there is so much high-quality stuff on offer if you keep your eyes open.
Do support local artisans. San Samuele, the area between Campo San Stefano and Palazzo Grassi, is crammed with superb jewellers, antique dealers, galleries and boutiques. Buying glass direct from the outlets in Murano can be tricky, so try Giordana Naccari’s Angolo del Passato, or the glass artist Massimo Micheluzzi for chandeliers and vases. Stationery is still hand-printed in the workshop of Gianni Basso (his son, a marine biologist, has just joined the firm).
Do keep to the right when moving slowly, allowing Venetians to overtake you—they’re not on holiday and know where they’re going.
Don't walk side by side (in doppia fila): most streets are too narrow for two-lane traffic.