I'm a firm believer in having the correct mindset when it comes to self defense weather you are armed our unarmed. Having proper mindset, proper training and the right attitude are essential. As I stated earlier, awareness and avoidance are the first steps. If you take these two items seriously (attitude) I believe that you will avoid up to 85% of possible confrontations. Some people don't like to hear it, but if stay away from the wrong types of places at the wrong time of day or night, most people can probably completely avoid violent conflict. This is just common sense but there are those guys who think that no one will stop them from going where they want to go. Okay, go ahead. But don't be surprised when things go south when you make that kind of decision.
Next, awareness is also crucial. I'm always amazed at how many people are so oblivious of what is going on around them. They look lost, preoccupied or have a cell phone glued to the side of their face and have no idea of what is going on right under their nose.
Bad guys don't play fair. They will not attack you on their terms. They will stack the cards in their favor. They don't care about a fair fight, they simply believe that violence will get them something they want. They don't want to look you in the eye and face off to see who is best. They want to hit you from behind with overwhelming force so that you have no chance to resist.
That being said not everyone you might have a conflict with will be career criminal. So some training will come in handy. Unless you are committed to training three days a week or more for the next few years, traditional martial arts may not be the best course. I also know that many martial arts schools train for sport and if that's what you want I've got not qualms. But remember you will react how you train. If you just train to score a point, guess what is likely to happen when things go south?
That being said I believe women should join a good martial arts school. Most women don't grow up roughhousing, wrestling, and playing contact sports. They don't learn the body mechanics to strike with enough power to do enough damage. Months of developing strength and muscle memory do wonders for them. When they discover that they can hit with some power its time to move to learning techniques.
Technique should follow the KISS principle, but things should not be too simple. And you should become well rounded. By that I mean you should learn both striking and grappling techniques. In truth about six to eight strikes with both hands and feet are all you need to know. But you must understand the concept of applying them. The thing about ground techniques is that you are usually either on the top, or on the bottom, and again, a limited number of moves is in order.
Learning techniques is great. But understanding concepts is far better.