As Bangsar is the place to be for KL people, the most vibrant place you should go to is to Jalan Telawi 3. this is an easily located area of the township as it is right in the heart of Bangsar. You will not miss it purely because once you reach there, you will be able to spot the place by merely looking at what is going on there. There will most likely be crawling cars with a lot of people standing outside and around the pubs which brimming with customers throughout the night. This is where you can choose between going for a drink or two with your friends in around the pubs, sit around at the cafe like Coffee Bean or Starbucks, or go dancing in the clubs around here.
Adjacent to this row is Telawi 2, which has its own version of entertainment outlets for you to choose from. The most likely activity you can spot around here would to start shopping at Bangsar Village, then rest your feet at one of the pubs when the mall closes, or hang out with your friends at the coffee places. Bangsar One, which is located a about 2 blocks away is an 'extension' of the happening crowd of Telawi where a row of bungalows facing the mainroad have been converted into food outlets and cafes and pubs.