Don't use colors for subway lines, they're only there to make the map easier to read. While some lines share routes along the way, they have different destinations. Only use the letter/number, and the direction. When you see several lines, it means you can take any of those to your destination. For example, Uptown N/R means you can take either.

And be sure to check B&H's web site for their store hours. They close early on Fridays, all day Saturday, and on every Jewish holiday.

Also, street addresses aren't used when giving directions. We use cross streets. B&H is at 34th Street and 9th Avenue. Your hotel is on Rivington between Ludlow and Essex.