At first you have to sure about your 'Interest'. Then create Profile in Social media and also create related page in social media sites(facebook page and google + page). Also create profile in relevant forum and put the link of your website in the profile. Contribute in the forum by asking question or by giving reply in your targated niche. Write quality content on your niche and share it in social media and let others give comment and criticise. Give your efficient reply on the topic. create profile on most popular social media sites.