Hello I need some help doing SEO, I have researched keywords. 1 main keyword + 5 category keywords. Wrote 5 articles 400+ words each about using category keywords and i have posted few of them to my blog. My blog and articles page are indexed by google. Anyway, now i want to start link building by blog commenting. Do i have to use category keywords instead of name? Do i have to add my domain url or url to my article which was writen using this keyword? Do i have to add link to comment aswell? Thanks..