A few tips I gathered from being a forum usual all over the internet.
1.Asking to be a moderator pretty much blows your chances of being one and making a thread about it makes things even harder.
2.Stay in a site long enough and you might get the position, but if you don`t,ranting about it will make things worse.
3.Report - if you are good at reporting people then you will be good at moderating too.Being a good citizen in the community alone won`t gain you that rank.
And a personal tip from me:
Read the rules, because this topic isn`t where it should be and becoming a mod is clearly explained in John(jmtb02) FAQ.