Link out to relevant and good quality content. Readers always love authorities who refer the right resources. They like to read more about a subject they are currently browsing. Outlinking Tip: Linking is like a respected professor recommending some books to his students. Obviously, the professor won’t risk his reputation by recommending the irrelevant, low quality or unethical books.
Outlinks should be part of your strategy to develop authority on the subject. Links are a vote for the content, relevancy and quality of the other site. You can build your credibility by letting users know that you read the latest on the subject and are interested in keeping them updated by recommending relevant and good articles to browse.
Another advantage of linking to quality sites is that by sending visitors to other sites and blogs, webmasters who track traffic to their sites will find out and probably recommend your site in return. A mutually beneficial strategy in the long run.
Don’t link out to spammy sites
Spammy sites are those that are illegal. Sites that use black hat search engine optimization techniques to draw visitors are also spam sites. They sell links to all and sundry including porn and illegal sites. Sites that obtain data about users and share them with other sites, without user permission are also spam sites. Excessive exchange of links is also considered spam. They may be downloading a virus or malware when you visit the site.
Selling outbound links affect Page Rank?
It’s not wrong to sell links. But if outbound links on a page are there because you have taken a payment, users must be informed. Remember, how Google shows paid ads as “Sponsored Links”. And you must use a "no follow" so that it's clear that it's a paid link. Page rank juice should never be passed on to an ad link.
Passing page rank to the outbound link page is not ethical. Kindly use rel="nofollow" when you sell links. This way you inform search engines that you are not passing page rank.
Linking out Does Not Affect your Site Traffic
Many webmasters and bloggers fear that outlinks will drive away visitors from their site or blog. That’s not true. Users will check out the other site, if it’s good they’ll respect your judgement. They’ll come back to your site for more. Wikipedia is the best example of relevant, quality outbound linking that helps create authority on the subject. Which is why users love Wikipedia, and Google shows Wikipedia pages for many search terms.