Santana knows whats up.
Granted I'm not a lady but when dealing with potentially dangerous people there are a few basic rules you should follow.
1.) Be polite even if the person is not dangerous you never know what they could be going through, and people can snap. Most likely you wouldn't get what you wanted that way anyhow.
2.) Be firm, confidence will give the impression you are someone who can handle yourself, and by showing no fear it make it seem as if you could defiantly defend yourself if need be.
3.) Don't talk politics too much, you may not have to be as closed as you would talking to the police, but peoples passions run very high when it comes to politics and you could turn a friend into an enemy if you aren't careful about that. Wait until the other person brings his/her political preference out in the open before you discuss yours, and if need be just nod your head. A stranger may take debate as an insult, especially when they are trying to help you out (pride is a silly thing).
4.) Do have something to protect yourself with, mace would be a good idea to have with you and if you don't have anything analyse your surroundings, this is something aggressive people tend to fail at doing, making the world around you one big baseball bat. I have never lost or got myself seriously hurt from an aggressive person because of just this.
and, you can always try and make yourself look like a boy

. Oh and if anyone asks, you have STD's. Sounds silly but if they think trying to sexually assault you will leave them sick they would be less likely.
Remember that it's fairly simple to get a good idea of a persons level of danger, just pay close attention to the way they hold themselves and the way they speak.
Also do not start anything with any body, and if some group of yuppie juggalos start cussing you out or whistling don't bother with it unless you absolutely have to.