well...social media is over-used more and more...again, with all that thousands of fake facebook accounts, for example.
Websites should be clean (e.g. free from wholesale links in the footer), well maintained (e.g. without big advertisements before title or h1 tag), well-wriitten updated content (for English language check it for grammar issues at spellcheckplus.com) and had some hundred of good relevant links, from websites similar to the topic of your website. Some social links, as well.
Time will do the rest.