New moderators begin with a Request for Comments (RFC) thread in About Unstuck. These may be started by anyone to nominate themselves or someone else. These follow the ratified process for RFCs, including the timings and votes prior to going be fore the community for a binding vote, which must meet a 2/3 threshold to appoint the poster as moderator. Moderators serve terms of six months unless they wish to resign earlier.
If a moderator wishes to be re-elected to another term, then within the last month of their term, they may start a re-election thread containing a yes or no poll that shall remain open for at least one week in About Unstuck, and they shall solicit an admin to make a banner about it. This is in lieu of going through the full RFC process again, although users may naturally state their cases for or against re-election in this thread. The moderator is or is not re-elected according to the same 2/3 threshold.
There are no limits on the number of terms a moderator may serve or on the concurrent number of moderators.