Automating your public speaking gigs should be treated like any automating any other high-end service.
You want to work toward having people pitch to you about why they think you should speak at their event.
You can do this by creating a 3-step application page, much like this.
If you’re looking to get started, you can get a few gigs under your belt by using a tool like this.
Learn more about automating your public speaking gigs here.