Make sure you publicise your seminar on your website or blog. Next, send notifications about your event to your email list. Promote your event extensively on social networking sites like Twitter, Facebook, LinkedIn, and Google+. Be sure to promote your event on site forums, or other online communities. Video is another great way to boost your attendees list. Giving people a preview of what to expect could entice them to attend. Lastly, don’t rule out the old school methods like sending out flyers.