Not as much as I should have. I had always been told that it was wrong to hit people, but at the same time going to the adults wasn't a thing you'd want to do. So in the beginning I fought back when the bully would provoke me with words and accidental pushes, but when I finally launched out at him, the people around us would force me to the ground. It didn't help that my bully had been my best friend up until school. The bullying continued for years and was too hard to stop since some weeks there wouldn't be anything and other weeks a lot and sometimes the bully would even be nice to me*. And again, words and accidental pushes don't really count as bullying, right?
In seventh grade (bullying started at around 2nd-3rd grade) a group, my bully included, decided to "joke" about me having sucked some nasty guy's dick. It hurt, of course, but more so since they'd "defended" me from the very same guy (they didn't like him and thus defended me when the guy had pushed me... it felt good to be defended). I tried to hit my bully, but the principal came by and I got an earful for it. I couldn't of course say to him that they'd joked about me sucking that guy's dick, so I decided for that one year not to be included in the class photo which I had been a part of every year.
Finally in ninth grade, the grade of graduation, I attacked him with all I could. We both took about equal amount of damage, but nobody interfered. That's when I knew I should have just done that earlier, I should have just kept attacking him whenever he did something, since he didn't do that much after that episode.
Up until graduation there had never been one person to stand up for me, and I had never stood up for anybody else either. Didn't help that my friends sometimes got friendly with my bully. Sometimes you didn't know who the bully even was anymore. It must have been around sixth grade or something that it all became too much and I took my belt around the neck and bound to the doorknob, so that I would get strangled when someone opened the door. The reason was that I accidentally and without knowing (I ran when he came after me thinking he was just "fun" mad so I didn't actually see it) had hurt my bully by throwing a hula hoop ring at him. The teacher took pity of him and I couldn't explain properly why I had run away and why him getting hurt a bit wasn't enough to make up for what he'd done.
In the end I couldn't trust teachers, I couldn't even trust my friends not to speak of my classmates. Someone should have to me that punching the bad guys is ok.
*It would have been easier to do something, I think, if I could have kept him purely as my enemy.