As Nashville continues to grapple with its mobility, one New Yorker has a piece of advice for the fast-growing city and its officials: just do it.

Janette Sadik-Khan — who served as New York City transportation commissioner under former Mayor Michael Bloomberg — said the best thing for Nashville to do is “try projects in the short term and see what’s plausible.”

Sadik-Khan was in town on Thursday to speak before a group of 500 city officials and business leaders at the Nashville Civic Design…