If it is your first time going I would recommend a service like the one mentioned from Landing Pad, there are also others. They get great seats and take care of logistics. It is more expensive but probably worth it.
If you have a high adventure level, go but go WITH an Argentine, at least the first time.
I went to see Boca matches a few times in the same section as the Barra Brava, nothing happened to me, basically people would ask where I was from and if Ioved Boca, to which I would reply "yes" and it was all good. ALSO the violence level depends a lot on who is playing. An international match tends to be very calm.
If you go only bring your id, ticket and small amount of cash for water and a ride home. no watch, cell phone, camera, etc.
That being said, these are places where going from "all good" too "disaster" can happen in a matter of minutes, you need to be able to read the crowd and react quickly, especially if you are in the standing sections.
I went when I was 21, probably wouldn´t go back now.