I noticed at my college that a LOT a girl are looking at me when I walk by. So here’s the question: How can I tell the difference if a girl is interested in me or just looking at me for no reason. For example, if you’re obese or whatever, most of the girls will look at you, but not for the good reason. I always look straight ahead when im walking but I can see from my peripheral vision that they are looking at me, and even the guys, seriously. I’m asian btw and where I study, there’s not a lot of asians. Should I try the “staring game” with everybody 
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Test. Go one day with mones and the next day without. See what garners more results. Even so, you should be and hopefully you are, acting on these perceived hits. Otherwise it all amounts to nothing 
Look right back at her - straight in the eyes and smile. An open, frank and friendly look/smile - And hold your gaze, do not stare.
If she smiles back, drops her chin (but still holds your gaze), or goes all coy/blushes beetroot red etc, then she is very likely to be open to your greeting her and maybe starting a conversation.
Easy.. as.. that..!
Also, if she does respond, don’t make the classic guy mistake of dropping your gaze and talking to her chest.
However, if she quickly breaks your gaze/looks away, physically turns away, recoils in horror or closes-up her stance/body language, looks like there is a bad smell about, then it probably best not to pursue.
Now do that on days with and without mones and hopefully, once you have found your sweet spots you will soon see the positive responses soar on the mone days.