Once I've got my topics narrowed down to two or three that I'm sure I want to run with, I start making notes about each one. My method for this changes occasionally. I've done this on 5x7 cards (which I use for many life tasks), sticky notes, something digital. Whatever works. I jot down some notes that help expand how the talk might play out.
Not quite bullet points (yet), this stage isn't that organized. This is thought-flow simply to get ideas out of my head and into the world. I can organize them later. This is more like a post-topic brainstorm session.
I also find it's helpful if I time myself on this step, no more than 10 minutes. Whichever topic ends up having the notes with the most legs to build a talk out with, wins! (And it's good to have the others as a fall-back, or future talk.)
Note: All tips written for my #talktips #30days challenge are written in 5 minutes or less.
if you have more questions or would like more info about any of my #talktips, leave a comment!