You collect stars by reporting emails with the Hoxhunt add-in. The amount of stars you can earn depends on whether you reported the quest successfully, if you missed the quest (reported it too late), or failed if you clicked on a link or opened an attachment in the quest.
TIP: You can follow your progress at game.hoxhunt.com.
Successful quest
Each time you successfully report a Hoxhunt quest you will receive two stars. You can earn a third star by completing the micro training.
Missed quest
Quest expires after four (4) days. You can still report it via Hoxhunt add-in but the quest is still considered as missed.
Each time you miss a quest you will receive one star. You can earn a second star by completing the micro training.
Failed quest
Each time you fail a quest you won't receive any stars. You can still earn one star and points by completing the micro training.