What else to do in order to do linkbuilding?

I have read around and concluded (from what I have read) that link building is the most important part in SEO..

So, these are some of the ways to build links that I have learned from my readings:
1) Directory submissions
2) Social bookmark
3) Buy links (the worst thing to do since many people said G will penalize)
4) link exchange (kinda 50/50 because some people say it's good and some say it's bad)
5) Article submissions
6) Link bait articles
7) Blog commenting on do-follow blogs

Is there anything else that I might be missing?

 

Find high PR dofollow site and leave constructive comment for 1 way link back.

http://forums.digitalpoint.com/showthread.php?t=660483&page=7

 

you can also try blog... and about buying links.. not all paid links violate google guidelines..

 

Thanks puzzle and for bogs, what type of paid links that do not violate google guidelines? I really need help to understand this part. Thanks!