how can i legally defend my self when a girl tries to hit me?

You can hold up your arm to block her blows while you back away, then turn on your heels and run. That's only defense a man may use against a woman.

Depends on details.

Normally you're allowed to use enough force to end the threat. You're expected to avoid physical confrontations when possible.

If this is at a school, most have zero tolerance policies for violence. They don't care who's to blame. If you anticipate a confrontation, you should be reporting it to the school in advance. If you're an adult, you can file a restraining order if you're having a problem with someone.

If she tries to hit you, pop her a$$ once in the face and trust me ,she won't try it again.

You dont have to. just take the slap and file charges with the police.

block her wrist with your arm.

You shouldn't have said or done something stupid that would have prompted her to hit you. The fact that she wants to hit you is a pretty good sign that you screwed up.

You are allowed to use equal force to discourage her - you must stop when she does.

Walk away?

No different than if it was a guy.

that depends on what she is trying to hit you with. you can either stand there and try to block the hits from her or leave where you are. if she is trying to hit you with some kind of weapon you can do what it takes within reason to defend yourself if you can't leave.

defending is one thing - returning an attack is another

WALK AWAY, that is how you defend yourself

No need to lower yourself to thug status

If she hits you you can legally hit her back