This is tricky, but key. If you hide your interest, you will most likely act weird.

And yes, rejection is part of the game and no problem. Unless of course - like you say - one is already broken. Then a simple rejection can be devastating of the remaining confidence.

Flirting is a game, but some never learned how to play. I also learned it quite late and remember the awkward teenage years and feel sorry for those who never got the chance. And nowdays it even seems harder.