the admin council chooses candidates when there is a need and if the candidates accept the invitation they are appointed as mods. we just got 2 new mods so it will most likely be a while before there is a need again, but i'm sure that the admin council will keep you in mind. bpbabe is right--no application, they choose someone who is knowledgeable and handles themselves well in the forum setting and who would fill in any empty spots in the current team.