You approach a girl and she gives you nothing... no words, no attention, nothing. Most guys will give up and eject the set pretty quickly. But you won't, because you know what a bitch shield is. You know that women have to filter and select men from boys, she has to know if you can take the shit she throws at you.

I've found that the most effective way to break that shield down is to risk being offensive. You don't directly offend the girl - that's just stupid - you give your opinion on what she is doing.

For example, I've been on sets where the girl I was interested in will ignore any words coming out of my mouth. As soon as I use the phrase "Hey! I don't like your attitude...", most of them will instantly open up. If it doesn't work you escalate a little bit - "I don't understand the purpose of being mean and impolite". If it doesn't work you escalate a little bit - "You don't have the looks to be THAT arrogant." And so on...

I seriously doubt any woman in the world won't break down their bitch shield after these attacks to their ego.

You have to know the difference between a bitch shield and disinterest. Calibration is key. If the girl stands there all the way through - it most certainly is a bitch shield. If she moves... well, you also move. You move on.