Cutting straight to the point , if she is interested in listening and laughing to all your stories from baseless to best selling type then just ask her out .Look I could have just given you thousands of scientific facts with reasoning and you may have left this tab more confident but believe me here not all girls follow the hints and are quite unaware that they are giving out signs being uninterested and I think you know how the friendzone forms..so make your move steadily just when her anticipation for you is high..Still if you are finding the techniques specifically thenHer smile should be realShe should stand facing you.Playing with her hair.Subconsciously following your gestures and ways.Playful touches.Hope it helps you and good luck.