Maybe you had a chance to give a speech in your school or you will do that . You must be stressed out. So did I. But my speech was successful. My experience would give you some advice.
First of all, you should practise it as much as possible. Practice makes perfect.
As for feeling nervous, you can tell yourself there's no noe listening to you, you're practising it to your own. Don't see the students below. My teacher told me this way and I tried. It was very useful.
The most important thing is that you should be confident. Believe that you are the best.
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