Impromptu speaking is unplanned but a necessity in today's world. Speaking coherently and clearly on the spot can affect confidence, and we don't know when it will happen. Toastmasters International gives "table talks" where a topic is picked and discussed using 5 methods: listen to the question, pause to let your mind digest, confirm the question, tell an answer, and conclude. The structure is simple: an opening tells us what your going to do, telling actually tells us what you're doing, and the conclusion tells us what you just said. The key takeaways are, whatever you do, be confident, be brief, and be sincere.