I write more, shinookubo sightseeing.

shinookubo is next to shinjuku station.

(I define shinjuku is around shinjuku Sta..)
shinjku is a name of city, so a it is similar to new york city.
When you're in Japan , we call shinjuku is shinjuku Sta..
But shinjuku is a name of address include kabukichou, ookubo, yotsuya, takadanobaba, kagurazaka, nishi-shinjuku, and so on.
so I wanna say
shinjuku is just like a only Manhattan , you been to new york city or just like that, you are not satisfied with shinjuku. shinjuku is just a "city".
Or you been to asakusa and kyoto to have enjoyed "japanese of japaneses’" ,
and you must think "japanese" is more than enough,
then you should go to shinookubo, there is very nice place, you might be satisfied there.

-when you are in shinookubo first time, you have to do is,

--eat samgyopsal( hereinafter samgyo' , sliced pork belly cooked on a tabletop grill)

---how to order
It is very simple to order samgyo' in korean restaurant.
when you be in a restaurant, you order samgyo' for amount of person.
you would like to have a drink , you order beer or anything else, that's it.
But you are a student anything else, in Japan, glass of water is free, it is not a legend but true , when you would like so , you say that " Omizu kudasai ".

And most of all korean restaurant serve "panchan", it means ”Appetizer”.
panchan is free in most of all, and some of restaurants would refill for free.

So you only order samgyo' and drink, that's it.

---how to cook and eat
after that you see sliced pork on the iron plate, korean lettuce "sanchu " and hot miso source and white onion, and panchan.

-cut (tear) lettuce size of your mouth
-put on lettuce hot miso-source(a little bit hot source)
-put on sliced pork have grilled
-put on white onion
-and you eat at a mouthful that's it!

very delicious meal, I'm not a korean but I love it.

Oh I forgot to tell you "tips" is not required in Japan, that's not a legend also.

I had better say where is restaurant recommendation, but korean restaurant is very changing, I mean so that there are many not good cases , name is not changed, but owner has changed, So quality is changed (yes,,not only these cases also).

but I dare to say recommendation,
"moise" and "suibokan", both are Okubo 1choume.
check Web site please, you install japanese character "モイセ" and ”スイボカン(水宝館)”.