“Umm…” is a filler word. When you give a speech or when you are presenting in class or when you are speaking, a filler word is used to fill in the gaps between one idea and the next idea.
When the transition from one idea to the next isn’t smooth, you will get stuck with that gap and you have the tendency to fill it with sounds or words that do not contribute any meaning to what you are trying to say.
Ideally, when you speak you don’t want to use filler words because they interrupt the flow of your speech and it shows that you are unprepared or incompetent in the ears of the people who are listening.
So how to remove the filler words?
Short answer: practice.
Long answer: Learn how to arrange ideas clearly in your mind, and connect those ideas smoothly with coherence speech on stage. That’s a long way of me saying that you have to get on stage and practice it there.
Plus, substitute the filler words with silence. If you need time to think and to connect ideas, then just stay silent. It’s uncomfortable, I know. I know because I’ve been there. But if you are confident in yourself, then silence won’t be a problem.
It takes practice, but you need to be confident in yourself first.