The question of "how do i tell if a girl is into me" is the most asked question by all guys and although there a lot of signs and reasons that i can give you to help you figure this all out, ultimately the decision lands on your shoulders to gauge how much this chick wants to be your next slam piece.
Here are a few very obvious and tell-tale signs that a girl is interested in you. NOW, just because i said interested does not mean this chick wants to take you into the next room and suck your balls dry. It simply means that she see's enough mildly interesting crap about you that she desires to know more. Now to the signs. Some very obvious signs include: her going out of her way to introduce herself to you, persistent eye contact initiated by her, her always smiling at you, her demeanor and actions will appear kind of nervous and slightly 'girly' to us men. Say for example you see this chick across the room that you may or may not know, and she catches you looking at her so you smile and she grins right back while playing with her hair, maybe shifting her weight back and forth, maybe she'll smile, look at the ground or to the side, then SMILE BACK again. This is a good fucking sign you are currently doing something right. When something is working well with the ladies, DONT CHANGE IT. Its when you over analyze what she says and does, and then make your own ridiculous conclusions and assumptions about what she wants that you then go an do, or say one stupid thing and shes gone forever.
Moving on, Body language is big. If shes constantly filliping her hair around to expose her chest, or to expose more skin in your direction, this is a good thing obviously. A BIG BIG BIG sign that something is going right for you is "The Touch". 'The Touch' is a very small, but important situation that may happen between you and a girl that you have not had any physical, or sexual contact with. This does not happen with a friend, this happens on a first date, or first time you meet this girl at a party or whatever. 'The Touch' is quite simply when a girl touches you in some way when you have never laid a hand on her before. It might be something as simple as a small pat on the lower to mid back, maybe she reaches out and slightly grabs your arm while looking at , she might touch your shoulder or leg or whatever. It simply is a motion of her going out of her comfort zone to invade yours and share some physical actions to get more endorphins and other good chemicals goin in our brains.
When txting, if she doesnt respond to a text of yours for like an hour or something, and the first thing she says when she txt's you back is "hey sorry i was...", she feels bad that she was not able to IMMIDEATLEY respond to your txt so she feels the need to apologize. This means that you are def on her mind and have some importance to her. Also, if you send a txt and get no response, dont send 3 more txts being like 'hey did you get that blah blah blah i look desperate blah blah blah ". One txt, One phone call and NEVER MORE.
If you are not getting a good vibe from this girl and she shooting down your requests, move on. There are 1249350983495834 more bitches out there that are dying to bump uglies with you so sac up, get over being rejected and find the next fish to fry.