How can I become more flirty?

I am a pretty serious guy and very kind. However, when it comes to girls; they don't seem to hold interest in the seriousness of my tone and overall persona.
I am very strong, smart and athletic. But how can I become more of a flirt, sort of connect on a different level than that of the pure obvious..
And by the way, girls you do prefer the flirt to the straight face honest dude right?
How can I become more flirty?
Add Opinion