How to be approachable with rbf and mildly defensive personality?

I have a tbh and I have a bad habit of glaring or acting disinterested at guys I think are cute because I don’t what them to reject me (counterintuitive Ik it’s an automatic reaction.) How can I become more approachable and open for guy to talk to me?
How to be approachable with rbf and mildly defensive personality?
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