Direct answer
Objectives follow journal display order. Some depend on your choices; follow the active objective in the game.
Result
Perusing a notice board in Toussaint, Geralt found the appeal of a ducal clerk. The clerk was seeking all manner of vagabonds, knights errant and mercenaries. The posting did not seem to be an offer of witcher's work, even so Geralt decided to learn more about this mystery job.