When you walk up to girl do not start the conversation by saying "Hi, my name is, blah, blah, what is yours?"
Sometimes that is way too personal, to begin with, and most girls don't respond well to these questions.
You can start knowing a girl, by asking a question relative to your surroundings that are impersonal.
Then based on the reply you get to move on from there. An example would be, if she knows the name of this song, or if she knows the name of the DJ.
You should avoid questions like "Do you come here often?" Girls don't like questions like this. If you stuck, and I know that it is easy to get stuck while talking on an attractive girl, check her and your surroundings to ask a few more questions, in order to win some time to think the next question to ask.
In some cases, you may want to inject a little humor. Girls love to have a laugh especially when they are out winding down from a tough day. They like a guy who is spontaneous and who can start a conversation without immediately asking personal questions. I wrote about it in a previous post, women don't like when people asking personal questions to them if first, they don't have a bit of rapport between.
So firstly the key to getting results starts with not being personal. Secondly maybe poke a little fun at yourself. Get them to relax and most importantly, make yourself relax.
Your goal is to build rapport. When you build rapport girls will become comfortable around you and as a result, you can start to get a feel for where they are coming from and find opening wedges for conversation.
You need to learn the fundamentals and build on your successes. Once you get the fundamentals right you can then get a little more advanced. The truth is this you will need to get comfortable with talking with strangers.
I know that this is tough at first but as you do it more it begins to get easier. So when you are out and you want to get to know a girl, first look for things that are going on around you that you can talk about especially if they will spark enthusiastic conversation. This will get you results without getting shot down.
But remember some girls don't like to talk to strangers at all, so don't cry if this won't work at first, you have to try it a few times.