The best thing that you can do to "prepare" her is to socialize her with people as much as possible. Dogs are not really that important, especially given the issue that you describe. The dog needs to be confident and outgoing. Confident dogs that are not afraid of people make the best dogs for your "protective" needs. Insecure, shy and cautious dogs will look to you for protection not the other way around. Unless, the dog becomes "sharp / shy" where it goes forward with aggression because it is insecure. Take her a lot of places to meet friendly people. Do not let anyone dominate her, correct her or even tell her no. That comes from you. Make sure you are clear with the rules when you meet new people, they can pet, praise and play with your dog, but the dog wins all tug of war of war games, especially with strangers.
If I can be honest, with out being too blunt, she may not be the best choice for a PP dog, IMHO. She is your dog and the first thing you need to do with her is get her confident around people and new environments. A 13 week old puppy should not be running behind you when she meets new people.
Be very careful to not "unintentionally" encourage this behavior. Never tell her it is OK, if she is nervous or try to reassure her. This tells the dog that that there is a reason to be nervous around strangers. I hope that makes sense. Telling a dog, "it's ok, don't be scared" actually enforces in the dog's mind that it is correct to be fearful. You are actually praising the dog for being in that state of mind.
Your dog is a baby, it is 13 weeks old. She needs to mature and gain confidence before you do anything else. I'd spend it's first year doing that before I sought out a personal protection trainer. You can not teach a 3 year old child to defend itself or you in fight, your dog is a baby.
Finding a trainer that will help you develop her confidence would be a great idea.
“Beware of false knowledge; it is more dangerous than ignorance”. George Bernard Shaw
Last edited by Slamdunc; 03-06-2015 at 10:28 AM.