1. Know how you feel
First of all, you need to take time to reflect on your feelings for this girl. Is it because of her appearance that you are attracted to her, or is it because you have the same interests with her in some ways? Do you want to be her friend or worship her? Do you really like her or do you just want to pursue her figure or company? Knowing your feelings is the first step to judge whether you really like this girl.
Observe your behavior
If you think you have a good impression on this girl, then you may behave differently in some ways. For example, you may often take the initiative to chat with her, or send her text messages, or try to exchange social media accounts with her. These actions themselves can't prove that you like her, but they can give you some clues about whether you really have feelings for her.
3. Try to associate with her
If you want to make sure whether you really like this girl, you can try to associate with her. You can invite her to go to the movies, have dinner or do something. In the process of communication, you can know her better and know more clearly whether you really like her or not.
Express your feelings carefully.
If you are sure that you like this girl, then you can consider showing her how you feel. However, you need to think twice before you act. You need to consider whether your feelings are true love or just good feelings. You also need to consider whether her feelings will be hurt by your confession. If you decide to confess to her, you should carefully choose the right time and express your feelings in warm and loving language.
In short, to judge whether you really like a girl, you need to consider your inner feelings, behavior, communication experience and expectations for the future. We must take our feelings seriously and respect others' feelings.