To share your photo, text, or video-on-demand post, click the Posts icon in the upper right corner of your event, and click the post you wish to tweet.
Click the Share icon in the upper right corner of the post.
You can either copy the given URL into a tweet, or click the Twitter icon at the bottom of the window.
If you do the latter, a window will pop up with the link to edit and share your tweet.
Your post will appear similar to the example below. When your Twitter followers click it, they will be redirected to the post on your Livestream event page.