Confidence, confidence, confidence. If you think too much about the consequences of what you do and say around her, it is likely that you will slip up and fail. In fact, don't think about that at all. If you think it is going to be the end of the world if she doesn't like you, forget about it until you lose interest in her. Then if you ever see her again get to know her at that time. Then after you regain interest, you can be confident around her and move in. Its easiest to gain interest by not being interested yourself.
Easier said than done.
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