Google have never revealed their ranking algorithm anywhere however many successful Internet Marketers and bloggers have proposed some theories and truths about google rankings. These theories can be used to understand google ranking tactics though these theories were proposed on the basis of trial and error methods but who cares about the source if these works perfectly fine to get high google rankings.
How google ranking algorithm works:
Here again I am going to give a statement with which many seo consultants will not agree at all. and it is,
The google dont gives much priority to content in google ranking.Because google crawlers or google bots considers even a meaningless self written paragraph as a unique content. Google uses crawlers not humans to crawl and examine your content and these bots can not explicitly determine the quality of content however they are able to decide if the content is copied,unique or spun.
so leaving content on a side we will discuss other factors that affect google rankings.
factors that affects Google rankings:
1. Quality anchored Backlinks:
Any blogpost can be ranked higher in SERPs by getting some targeted keyword anchored backlinks.
Suppose we have a blog post on our blog "how to incerase pagerank of a blog".
And if we want to rank this post in SERPs for keyword "increase pagerank" then we need to get some backlinks to our root domain and some to that post page with anchor text "increase pagerank".
Note: The format yourname@keyword is only recommended if the blog on which you are commenting is a keywordluv blog, dont use this format of anchor text while commenting on non keywordluv blog instead use your targeted keyword directly as anchor text.
Check out this high pagerank dofollow blogs list.
2. Backinks diversity:
Let the flow of backlinks to your blog diverse, google loves backlinks diversity.
Get targeted keyword anchored backlinks from veriety of resources such as blog commenting,guest posting, article directory submission, wiki posting etc.
Also read this article to check out how to get maximum from guest posting.
3. Bounce rate:
If your blog have low bounce rate and users spend relatively more time on your blog then google considers that your respective blogpost content is usefull and totally revalent to the search query by which the respective visitor landed on that page.