When building links for search engine optimization purposes, the best thing you can do is to make your links look natural. If you are actively building links to your website, you want to make these links look like people just decided to link to your website because it has good content. Since search engines increase your rankings for having natural links while they can penalize you if you are buying/selling links, it is important to cover your tracks.
One of the most common mistakes when building links unnaturally is to use exactly the same anchor text, for example a keyword phrase you are targeting, for a large number of links. If your links are natural, there is a very slim chance that everyone that links to you will use identical anchor text, and the search engines know this. If you use variations in your anchor text, your links will look more natural. For example, if you are targeting the phrase “internet marketing consultant”, when choosing anchor text for new links, sometimes use “internet marketing consulting” or “consulting for internet marketing” and other variations.
Another issue is your link growth. If your site has never generated more than five links in a month, then all of a sudden it generates 200 links in a month, this can look very unnatural to the search engines. If you are starting a linkbuilding campaign, start slow. Each month, try to get a few more backlinks than the previous month.
The key to a successful linkbuilding campaign is making the links appear to be natural. If you can accomplish this, you will see much better ranking results.