1 - Don’t assume that people in New York are cold hearted grinches.
Stereo types are deceiving and the people of New York can be some of the friendliest people you'll ever meet. As with all people and all areas - treat people the way you want to be treated and they'll welcome you with open arms.
2 - Don’t make plans all over New York without considering travel time
New York is deceivingly large if you've never been there. It's best to try and stay in the same borough or neighborhood when you're visiting to make the most of your time there.
3 - Don’t go to Times Square in the middle of the day or even in the evening
Times Square is a very busy place during the day, but to really see it at it's most majestic and not be plagued by the crowds, wait until after 11pm. Better still, plan on being there after a night on the town which can last until 3 or 4 am.
4 - Don’t eat at McDonald’s, Olive Garden, or other large, corporate fast food establishments
One of the most amazing things that New York City has to offer is it's eclectic and diverse choices of food. Take your time and dine in some of the most adventuresome eating establishments that the world has to offer.
5 - Don’t rely solely on credit cards and debit cards
As eclectic as the dining is in New York the shops are just as diverse and many don't take any type of cards. Make sure that you've got cash available for many reasons.
6 - Don’t hang out or walk slowly on the left side of the sidewalk or escalator
The unwritten rules of the road hold true to the unwritten rules of New York City pedestrian traffic, Unless you're passing someone stay to the right.
7 - Don’t accidentally go on the express subway
Express subways skip some local stops and go to the more used destinations. If you're going to a local stop you could miss it altogether so be aware and if you don't know, ask someone.
8 - Don’t tip 15%
15% might be standard where you're from, but in New York you want to be tipping 20%. Don't think of it as robbery, everything in New York is terribly expensive to live so consider it a cost of living increase when you visit.
9 - Don’t forget to tip the street performers
Street performers can make you smile, laugh, hum a happy tune or even think of something differently. Be nice to them and help them continue to spread joy to everyone.
10 - Don’t forget to use the toilet when you can
Unfortunately, public restrooms are not readily available like they are in Europe and elsewhere. Don't consider this lightly, when you have to go, you have to go, but be aware that even some McDonalds have bouncers in the bathrooms.