In the previous article on this topic, I covered the main types of links you want to get for your site. On the last part, I will clearly state which types of links to stay away from pursuing, and I will further explain some misconceptions about the good types of links.
Do not do this to your links.
(1) Placing a form on your site and then allowing anyone to add a link to your site using an automated process. If you do not manually approve these links, well, you are asking for link problems. Manually approve these links before posting them. What works, takes work
(2) Denying a link based solely on a low or non existing PageRank. What a mistake! PageRank is not only outdated, it is also less relevant that it was in the past. As long as it is related to your site, what really matters here, is that the site your are reviewing is indexed or not. That is the key issue, not its popularity. This also applies outside the regular sites circle, to niche directories, smaller engines, etc.
(3) Sites that exchange links with you, but at a later time they do a nofollow on your link, or they just simply take it down. That is why you need to check your backlinks...