now, is it 30 activity to become a junior member? and are campaigns for junior members or mostly for members and up
Yes.
There are only 2 campaigns for newbies and jr members, and a few more for members+.
Please check
https://bitcointalk.org/index.php?topic=615953.0 for everything you need to know about those sig campaigns.
777 is my best choice as a junior member, but how do i join their campaign? do i have to make an account with them or what
1. Go to their sig thread (
https://bitcointalk.org/index.php?topic=654009.0).
2. Copy the sig code and paste it in your "Signature" field in your profile. You may register an account on their site to claim ref earning.
3. Put "★☆★777Coin.com★☆★ What are you waiting for?" in your "Personal Text" in your profile.
4. Make a post in that thread with your bitcoin address and your current post count.
5. Make at least 20 constructive posts a week to get paid.