What should I do ?

You're going through a very common problem for guys. Being shy to talk to a girl and not knowing how to deal with it.
I'm not the most confident guy when it comes to girls, but I do have a lot of tips I can share with you which I've learned from my own, as well as other people's experiences.

Firstly, when going into the conversation, just walk up to her and greet her. Most conversations begin with a simple, "Hi", "Hello", "How are you" or any greeting. Greet her like you would any other people. Keep your cool and speak calmy and confidently(but not arrogantly or boastfully).

Conversations usually start with a greeting, and then open with a question. Try asking her, "do you need any help with that?" if she's doing something or "How's your food?" if she's eating. There are lots of possible situations where you could approach her and I can't tell you the exact words for all of them, so just let it all come to you naturally.

When your conversation starts, make sure to be the listener. Girls are usually the ones who like to open up about their emotions and the way they feel, because they're usually more emotional than guys. So, she's really gonna appreciate it if you listen to what she has to say. You can give your own responses or thoughts, but make sure to be a good listener to show her you care about her.

Show a happy personality. Smile at appropriate moments to show her that you enjoy her company, and she will most likely enjoy yours as well.

You can also throw in a joke or two into your conversation. Lots of girls admire a good sense of humor. But don't think too much about joking around. You might end up saying something dumb, stupid, or even worse, offensive.

Lastly, be yourself and be nice. And when you've finally become her trusted friend, don't go too fast into trying date her. Take it slow so you won't scare her away.

All this guidelines I'm giving your are exactly that. Just guidelines. Reading this won't immediately guarantee your success. What will determine if you succeed or not is how you handle every time you spend with her.

This has been your boy, Nyjel Tyger!
Best of luck to you, dark101!

"Giving up shouldn't be an option when it comes to love. If you give up so easily, you shouldn't be in love in the first place." -Brian Puspos