I'd love to visit New York City someday. But I understand that it's important to first learn a few points of etiquette, such as not stopping on sidewalks. Well, I get frustrated when people do that anywhere. So I can sympathize with New Yorkers who get irritated at tourists clogging traffic.
What else do I need to know? Valentine's City of New York: A Guide Book, published in 1920, will fill me in. Here are a few samples:
Don't ask a pedestrian where a certain street is. He is usually too busy to stop, and if polite enough to stop, won't know. No New Yorker knows anything about New York. Consult this Guide.
Don't cross the street in the middle of a block. In Paris they arrest you for doing that, in New York they simply run you down. Use the corner crossings only. Traffic police guard important crossings. "Stop" and "Go" as they direct. […]
Don't buy the Woolworth Building, Brooklyn Bridge, the Metropolitan Tower, the City Hall or any prominent structure because a stranger happens to want to sell it to you for a few hundred dollars. Buy Thrift Stamps instead. […]
Don't gape at women smoking cigarettes in restaurants. They are harmless and respectable, notwithstanding and nevertheless. They are also "smart". […]
Don't block the sidewalk. New Yorkers will gather in crowds to see a young lady demonstrate a new razor in a shop window or a safe going up the side of a building. Ignore such gatherings ; show our ex-hicks that you come from a real town.
New Yorkers, is there anything that you would like to add?
-via Nag on the Lake
This advice should prove to be timeless.