There's a specific thread you can visit here it is:
https://bitcointalk.org/index.php?board=238.0Here's the step on how you're going to join a bounty:
1. Visit the bounty thread (See the link above)
2. Find an open bounty campaign
3. Read the description in that campaign the format is like this (But not all)
• Description of the project
• The % of the bounties
• The description of the different bounties and the rules. Commonly there's a format for you in order to join the campaign and you're going to post it in that thread here's some of the description you need to give (This is just example follow what's on the format of the campaign)
-BCT name
-BCT url
-Wallet address
• Spreadsheet (The list of the accepted users)
4. Wait till your name is on the spreadsheet.
5. Do the job and wait till the ICO ends and earn your stake.