Backlinks aren't just doing article submissions,bookmarking and the 100 other methods out there. You should focus on the Quality of the backlinks and not the number of links. 1 link can give your site more "Link Juice" than 100 links if that one link is high quality and the others are not.
When talking about backlinks they're several factors to consider. Not all links carry the same weight.
1.Link velocity= the rate at which you build links.
You want to start out slow and build your way up. You don't want to build 1,000 links this month then none the month after. Then the 3rd month build 10,000 links then the 4th month none. G wants your links to look natural. So make sure you build at a steady pace.
2.Backlink Profile= where your links come from.
You want to diversify your backlink profile. Meaning you need links from several different methods(articles,bookmarks,etc) as well as different ips. It will look unnatural to G to have only bookmark backlinks and no other kind of links or backlinks from the same ip. G knows naturally you would have had several kinds of links not just bookmarks and ips.
3.
PR/Authority=the better, the more weight passed
PR and Authority are not the same thing here. You can have a high
PR site that is not seen as an Authority in the Search Engines. Higher
PR backlinks give more weight than several
PR 0 links.
4.In-Context backlinks are better than any other kind of link, since the Panda Update.
This should get you started as I don't have time to keep going on right now.
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