When you're developing a short-form talk or a talk of any length it all starts with your core idea.
Your core idea is the central point of your entire talk. Everything in your talk revolves around this one idea. Your core idea is a sentence. It is the shortest way to describe your talk. If you had to take your entire talk and condense it down into that one idea, it would be a short sentence. Not a sentence with a lot of and's and but's and going on and on and commas. No. It is a very short sentence.
And that sentence then gets expanded out and the entire rest of your talk is going to justify that core idea. It's going to justify why this core idea matters and why this core idea matters now.
Oftentimes, people think that their core idea and their titles are the same thing. That's not usually the case and it's actually not ideal. For your title, you'll want to save that because you want it to have intrigue. You want the title to serve the purpose of drawing people into your talk and of making them curious. "I wonder what she's gonna say? I wonder what he's going to talk about?" So you wanna add this kind of level of interest into your talk.
For your core idea, that should be very clear. That should be exactly what you want the world to know. And this can be based on your personal experiences in life, your background and the adventures you've had in your life. You want to have the core idea unique to you. It should be a little catchy so people can remember this. You want people to be able to actually remember and repeat your core idea again and again and again.
That's where your talk starts. If you don't have a core idea, you don't have a talk. So start with your core idea and build your entire talk from there.