Is is ideal to send at least 3 different messages to promote a specific live event. One beforehand, one the day of the event, and one afterward as a follow-up
For example, news item "Patricio Whittingslow will give a talk at GopherCon LATAM".
Here are 3 social medial posts to send. In the actual posts, you will want to use the "@" addesses instead of the name if available, to facilitate reposting.