For womens' self defense there are a few techniques that I favor most. Breaking items such as the knee, ankle, neck, elbow, these are all really effective. One, because you damage the assailant, two, when you break something they are less likely to follow you they are less likely to run you down so you can break, run away, and escape. To break the knee you need to come at one of four angles, actually five angles. Basically you come to the knee as across, across here, so you can hit up and in to the side, up and in to the inside, down and in, down and in or straight back to lock out the knee. When you use that coming up and in with a front snap kick use the ball of your foot again here or straight in here or if you want to come on to the inside of the leg use your opposite leg and come up here or in and down, here. As you can see that locks out the knee and if you use that full force with the kick, boom that will break the knee allowing you to escape.