Reading body language is an important talent that some people have. One way to determine if a girl likes you would be to observe her body language. Usually, the words she says can’t always be trusted based on the fact that she might be either letting you down easy or she is just a nice person. Therefore, look for key details in what she is saying. If she has good eye contact with you, she may be into you.
Other details to observe is if she initiates speaking to you. If she looks at you from across the room, then she probably does like you. The best way to determine if she likes you or not is if she is beginning to communicate with you.