I would recommend seeking out additional training...Have you checked out the book recommended by MattInFla (from your McDonald's post)? There is no cut-and-dried answer, just general guidelines....know the law, seek training (to learn defensive techniques--in include when to NOT draw your gun), and practice what you've learned.
Carrying a gun is no guarantee against bad things happening to you....that there are HUGE implications for carrying/displaying/drawing/shooting a firearm for self-defense. It's not like TV...a shooting happens and a couple of hours later you're at home having dinner. You have the firearm...now you need to get your defensive mindset ready.