To get a head coaching job, you need rep. How do you get rep? Simple, post interviews and media updates and all that media involved articles about your coach. You control whether his rep go up or down. *Note that the post has to be worth reading and a good length.
Example:
Post about your coach paying players to hit hard = rep down
Post about your coach attending an autograph signing event = rep up
Post about your coach messing around with a cheerleader = FIRED!
Enjoy playing with your coaches rep