Any suggestion is appreciated.
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Most Helpful Girl
Why would you want it to not be obvious? Isn't that counter productive? It kind of cancels out making your interest known.
I advocate girls asking guys out, but if you really don't want to I think you need to be as obvious as possible; just like you, most guys are afraid of rejection, and many won't ask you out unless they're positive you like them back. So, flirt away.