I've had many years of moderating experience on several different message boards, and there are a couple different things that always stand out (for both people wanting to be a mod and people looking for mods).
Not asking to be a mod is usually a pretty big one (unless there are specific applications, of course). The reasoning I have behind this is that people who know they are being looked at to moderate will often act better than they normally would. As an admin, you want to know what kind of members these potential mods are going to be. If someone is asking to be a mod, you'll know they'll be on their best behavior. They end up being less likely to be chosen than someone who never says anything.
I would also mention to not backseat mod or report every single post that is remotely against the rules. Backseat moderating is just annoying - you're not a moderator and it often isn't taken well by other posters. Reporting every post is similar in annoyance. In my experience, overzealous mods usually A) don't last very long, or B) have conflict with members. What you need is a good balance - keeping the peace while making sure the rules don't get broken. The people who report every single thing they see are often not the best choices for moderators.
Another big one - be active, but not overly so. People who post once or twice a week? Probably won't get chosen. People who post 10 new threads and reply to 100 others every day? Probably won't get chosen. Visit daily and post in a variety of threads and forums, all over the board. Show yourself as someone who is interested in more than just the Trivia section. ;)
Show and share your knowledge. This is a Pokémon board, so, it would make sense to be knowledgeable about Pokémon. It is also a vBulletin board. You should make the attempt to learn at least the basics of how the forums worked. Share this knowledge with others too. After all, in the end, mods are serving the members of the board. Old and new members alike are very likely to come to you with questions, from how to set an avatar to how to learn scripting. If you are able to answer the question or direct them to someone who does, you're starting strong.
Have a personal touch, and be kind. I've seen many members snip at each others or simply write rude, disrespectful posts. Look at it this way. PC is a business. As a mod, you would represent this business. If you go to Sears or JCPenneys and a staff member is rude to you - you leave. Be respectful, even if it is someone asking the same question for the millionth time or breaking rules that often gets broken. If further discussion is needed, keep it to PMs, but just remember - if you become a mod, you are representing PC. I'm one of the first to admit that this can be difficult, but this is how it works at any business. Just because you are trying to get a volunteer position, doesn't mean that you don't have to put as much effort in. One of the most important takeaways from my business classes is that the customer is your most valuable asset - without customers/posters/readers/even lurkers, you don't have anything.
Most importantly - make sure you really want to be a mod. As some have said, it's a lot of responsibility, and the only perks you get, really, is some recognition. You are expected to do a job, for, in reality, little benefits.
Let me give you a quick run down of what I did at the last board I moderated on (about 5 years as a community staff moderator and team manager, about 300k members). My duties involved:
- Making sure rules were followed.
- Writing and updating rules.
- Starting and continuing discussions, if needed, ending them.
- Reading new posts and replying as needed (to answer questions, facilitate discussions, etc)
- Moving threads to proper forums, closing, splitting, and pinning threads when needed.
- Welcoming new members.
- Banning, warning or suspending members.
- Answering questions sent by PM.
- Being aware of what is happening in other forums, and making appearances there.
- Help plan for the next stage of the boards - I wrote essays about changes that needed to be made, things that were going well and that weren't going well, etc.
If this doesn't sound like something you can handle, don't try to be a mod. :P
Wow! Essay! This stuff is pretty interesting to me though, and surprisingly, has become more interesting since I left my moderating positions at other boards. Those would be my basic notes to someone who wanted to become a moderator, though. And yes, they would be that lengthy because if you want to be a mod, you better be good at reading! ;)