> Use PR and social media to generate good backlinks for your site. - Use social media like reddit, pinterest and others as well as facebook and twitter. -
FB, Twitter and Reddit may not mark external links as "nofollow" explictly (which would kill their backlink value), but searc engines are smart enough to reduce the power of these links as these are "user-generated content" links and are less valuable as they're not authored by the "site owner" in the way a blog post or web page would be.
The impact of these links on social isn't zero, but it's not great either. You're better off trying to get qualified, organic traffic to your site (say from a backlink on a related site or from an email newsletter) as those clicks will likely have a lower bounce rate, which is good for SEO.