What self-defense should a woman learn first?

Not a fancy technique. The first things are unglamorous, which is exactly why they work.

Distance and awareness come before anything physical. Most trouble announces itself. Somebody closes the gap. Somebody gets between you and the exit. Somebody asks a question they do not care about the answer to. Feeling that early and moving is worth more than any wrist lock. Hands up in a natural position, angle away, keep space. That is a skill and I drill it like one.

Voice next. Loud, low and simple. A short sentence, repeated, that tells anyone nearby exactly what is happening. Most people go quiet when they are frightened, so you have to practise being loud or it will not be there when you need it. That is the bit women skip in class and then wish they had not.

Then grips. Breaking a wrist grab, a two-hand grab, a bear hug from behind, a hand in your hair. The principle never changes: move your whole body and not just the arm, work against the weak part of the grip, and go the second you are free.

Then staying on your feet, and getting back up fast if you do not. None of that takes a year. See what a few sessions actually covers.

All of it assumes the other person is bigger and stronger, because they usually are. That is not a reason to skip the physical side, it is the reason the physical side is taught the way it is: leverage, angles and the exit instead of trading force. See what to do when the person is bigger and stronger.

And the whole list sits under one idea, which is that not being in it beats getting out of it. Why avoiding trouble beats winning is the part people skip and should not.

Get those and you are ahead of nearly everybody. See what to do when someone grabs your wrist and what you can train.