You will need
  • Attention to detail
Body language
Make eye contact with any girl. If she looks away, her pupils dilate and her eyelashes tremble, it is not a joke you are interested.
Look at her legs when she sits. Except that that in itself is a very pleasant sight, it is also signaling system. If she is sitting, legs crossed, and toe of her shoes pointed at you, if she shakes her leg, she clearly shows that she wants you moved up a little closer.
A flirtatious turn of the head, hands, pulling hair or jewelry, sleeves that folded higher and higher, exposing the wrists, telling you that she is nervous and asks a question: he likes me, do I not like him? Why is he not doing anything?
Pay attention to her voice when she speaks to someone. Does he when she speaks to you? If she tries to adjust to you, begins to speak faster or slower, quieter or louder, it is a good sign.
Whether it says more about myself or trying to learn more about you? By itself, such interest may be simply a manifestation amazing communicative girl, sincere interest to the interlocutors, but together with other signs is another sign in your favor.
If she asks you about your ex-girlfriends? This interest may be due to the fact that she's trying to figure out if she's your type. If it is a lot of detail and talks about his former, now she probably needs a friend and companion, not a guy.
If she's talking to you casually making plans for a future together, for example, says "have You seen this movie? Come on, we have to go!", it is unclear what are you still waiting for? You definitely love her, but your indecision is just beyond us. Does she have to do everything for you?