Speaking Naturally In Public

Suggested Video.
Think Fast, Talk Smart: Communication Techniques. 

The video is almost an hour long but worth the effort (you can skip 43.40 to 45.30) - Catching peoples attention.
  • The need to practice communicating.
  • Managing anxiety.
  • Staying in the moment.
  • See things as an opportunity.
  • The power of listening.
  • Always have a structure.
  • Tell stories.
Health and Wellness.
I recommend you check-out the speakers website nofreakingspeaking.com.
  • Keep calm:  This is not only important to you as the speaker but to your audience.  If you are anxious they will be anxious.
  • ​Become aware: Talk to the audience not at the audience.  You need to be aware of the audience reaction in order to be sure you are actually communicating what you wanted to communicate.  I have on occasion found myself speaking to non-receptive audiences (most high school teachers will empathise).  I have found that in almost every instance it's a waste of time to just keep going.  Over the years I have developed devices that trick the audience into listening.  The one I remember well was telling an obviously disengaged group that I had been in a rush and had not been told what I was there to talk about.   I asked them what the the talk was about and what was it (within this) that they thought was important.
  • Be yourself:  Structure is important and knowing your subject useful but both come second to being yourself.  All communicating spontaneously has to be an extension of your personality.  A small example of this is that if you hate telling jokes in your private life they will almost certainly fall flat if you try it in public (watch from 55.30 on the video).  Novelist and poet Mary Anne Evans (George Eliot) warns that relationships can be strained by ill suited jokes.
  • Be happy:  Embracing what you are doing will help pull your audience along to the point where they start rooting for you without realising it.
Suggested Videos.
Impromptu Speaking Frameworks.
Impromptu Speaking.

What's Next?

If you want to sound natural when you have to talk, unexpectedly, you need to start practicing. It is very important that you practice speaking out loud (ask my long suffering wife, friends and children).  

Over the last few years I have watched colleagues get great results from Toastmasters, an international organisation dedicated to communication and leadership development. Whatever you choose don't let your audience be the first people to hear your presentation/talk etc.
Arrange a 'Public Speaking' online group workshop.