Bounty campaign has different campaigns like signature, translation, and social media campaigns, you just need to apply on every campaign that you'd like to participate in. But to be able to participate in social media campaign like Twitter and Facebook, you have to reach their minimum required followers for every account that you have. And in signature campaign, some of them are not accepting newbies and even jr. members as a participants, you need to level up first your rank to at least member rank to be able to participate.