There are different ways to tell if a girl likes you. Body language is a very big factor and can tell you a lot about how she feels if you know what signs to look for. Her stance tell you a lot. If she likes you, she will usually face in your direction. Eye contact is also a big sign. Girls who like you tend to try to look deeply into your eyes and hold your attention. If she also smiles and looks down, then she likes you.
Does she randomly hug you? This is a big sign. Another trickier sign is to see if she copies your movements. This is a subconscious movement that happens when someone likes you a lot. They will copy your body language without even realizing it.