I have this problem all the time, haha. I can say from experience that it depends on the kind of guy. I will tell you some examples of guys I have liked.
The more shy, kind, and considerate guy. Chances are he is as nervous as you are to talk to him. This will be with almost any type of guy but try to become his friend first. Once you become friends with him, maybe try some light flirting. With the shy guy, he may react in a way that seems like he will reject you. If he reacts like that, just stop flirting and stay friends. The best way to see if he likes you is try physical contact. If he tells you a joke, playfully nudge his arm or something. I know it sounds cliche but it works haha.
The rebel guy. The guy who skips class and breaks rules. There's always a catch with them. They don't show their soft side. Become friends with him. Hang out with him and try to find his soft side weakness. Once you do, playfully use it against him. I have seen this happen and a lot of the time he sees it as a playful thing.
In the case with any type of guy, your best bet is to become friends with him. Close friends. Then, start the flirting. Subtle at first but if he is oblivious, go all out hahaha.
Love y'all! I hope these help you out, let me know!!!
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