Social media activity usually spikes during a presentation as people are broadcasting your ideas. Usually there is only moderate chatter beforehand and afterward. Facilitate the conversation while it is at its peak by doing the following:

Streaming your presentation: Post a live video stream of your talk so people can attend remotely. This is the most direct way of extending your reach online, because the full message comes through, not just the chatter around it.

Time-releasing messages and slides: Craft messages and slides expressly for social media channels, and use technology to automatically push them out at key moments during your talk.

Selecting a moderator: Assign someone—a colleague, a guest blogger, an audience member—to keep the social media thread constructive. Pick a person who’s quick-witted, with a strong command of your material. Ask her to tweet key phrases as you say them, raise thought-provoking questions online, and bring the chatter back on topic when it starts to stray. Also have your moderator send out links to your hand-outs (post them online or as PDFs on your website).

Repeating audience sentiment: In addition to broadcasting your message, the moderator should repeat (and spread) what live audience members are saying during your talk. The currency of social media is reciprocation: so by spreading the ideas of others, yours probably will spread too.

Posting photos of your talk: Enlist someone to photograph your presentation. This gives social media users images they can post immediately, he can work with your moderator to post the images while you’re speaking.

Encouraging blogging: Invite bloggers, journalists, and social media specialists to attend and cover your presentation. You’ll increase your reach exponentially through their outlets and followers.

Contact Duarte