Right now, we aren't looking for any new editors.
When we are, our first choice is to nominate people we have worked with- people who create fine, error-free quizzes and who have demonstrated that they have the personal skills necessary to work calmly and compassionately with a wide variety of quiztakers, some of whom may be very young, non-English speakers, rude, etc.
If we still have positions open, then we do announce an application process here in this forum. This is quite rare; I think we have done it twice in the last five years or so.
Not everyone who has been around a long time and written lots of quizzes will be invited to be an editor. Don't take it personally.
Senior Editor and Site Administrator
"I'd rather make one dog happy than please all the dogmatists in the world."
P. Z. Myers