Dress warm and be ready for winds - the cross winds coming down a street or avenue can be very strong. Wear a hat and make sure you have bottled water. Good and comfortable walking shoes too. City Quilters is at 133 West 25th street, between 6th (Avenue of the Americas) and 7th Avenue. Its a nice little shop if you have time to get there.
The Empire State Building is at 34th street, that's a cool thing to see too. And of course not far from there is Macy's
I have a funny feeling that your trip is already filled with plenty to do
Enjoy! Oh, and just to be more comfortable, don't carry a purse but rather wear something small to keep your money and such in that you can wear under your coat. That way you don't have to worry about setting it down someplace.