Right before you take those last 3 steps up to the girl you're about to open, before a single word comes out of your mouth, just take a full, deep breath.

This has several benefits:

  1. It clears your head and gets you into the moment

  2. You have more breath so when you start speaking your words are fuller and sound more confident

  3. It inflates your chest making you seem a bit more manly, and naturally improves your posture