Before joining any bounties you should have at least twitter and facebook with 100-200 followers. But in most cases it's better to join bounties when you have more than 1000 friends, then you'll get more stakes even if you join later. Almost all bounty campaign freeze the number of your friends/followers till the end of ICO. For example, you worked for 5 weeks and got 1 stake per week. And another newbie joined bounty on the 5th week and got 5 stakes per week, cause he has 1000 followers.
Can you you explain me what is Stakes? I'm newbie too. 1 stake =?