You know someone who could tell us interesting things at the congress? You recently read an article and thought “It would be great to hear that person speak at the congress”? But you are not sure if he/she/it knows about it? Then just tell them!
There are many ways to do that, the easiest one would be sending an email like this:
“Hey [name], I like your [article /talk/project/something] and I would love to see you at the 29th Chaos Communication Congress. You can find the Call for Participation here: [link]. If you need any help with the submission form I would be happy to assist you. Be aware that the submission deadline is September 30th!”
Of course it would be much nicer if you wrote some more:
You could write some words about the congress: you can use the Wikipedia entry or the older congress pages for copypasta. It will be even nicer if you find your own words. You can also point out that a lot of great people have spoken at the last editions of Chaos Communication Congress, and this would be a good opportunity to be listed on the same page with those people ;)
Please make sure that the speaker does not get the impression that you are from the content team or that you are issuing an official invitation.
You could also write to email@example.com and suggest a speaker. Tell us something about him/her and how great it would be to have them! Give us links to talks he/she held and just everything we should know to invite him/her.
Let’s build a great congress together!