I got it right after I turned 18. We had to sit a an auditorium and they assigned us a number. When they called your number, you go for the interviews with the lawyers in the courtrooms. Until they call your number, its pretty boring. Bring a book or something. Then the lawyers ask you a bunch of questions and decide if they want you on the jury.
I actually got picked for my trial and had to go for the next three days after that. You get paid like minimum wage or something... It sucks, but that's civic duty for ya...:rolleyes2