Short answer: Don't!  To anyone but local Venetians themselves, Venice might as well be a labyrinth. Built over an archipelago of 118 islands linked by bridges, the city is a real challenge to accurately navigate that one might as well purposely wander around and trust in the gods to find the way back home.  * A few random turns and we find the infamous Bridge of Sighs (in the far background). Local legend has it that it was called so as this was the bridge leading to the prison from the Doge's Palace, and convicts were known to "sigh" as they got one more glimpse of the beauty of Venice before being incarcerated.