Need A Suggestion Please!!!

I have a blog with 12 posts and 12 keywords (low competition). I want to rank all post. I have learned many things from here but stuck on some basic things.

For 1 post I made 5 web 2.0 , 5 doc share, 6 image share, 1 video, 5 social bookmark, 6 profile backlinks. total 28 backlink for tier 1.

1. Do I need more tier 1 backlink?
2. Should I do tier 2 for all 28 tier 1 or only for web 2.0?
3. Do I need to do same things for all other posts?
4. Can I use same tier 1 account for all posts? Or…

Need A Suggestion Please!!!