Practice
Rather than read from a sheet of paper or off your notebook, learn your content by heart. Practice what and how you are going to say at the presentation. This will make you look confident and prepared while also getting you ready to face the audience with your material. And knowing that you're fully prepared will tone down some of that nervousness building inside of you. Practice really makes you perfect.
Be honest
Don't be afraid to admit when you don't have an answer. You can always redirect the question back to the audience, and if someone has an answer, they can inform everyone. This is much better than just speculating on the right answer. And if you do get something wrong and someone corrects you, don't hesitate to apologize.
Learn from someone you admire
There must be someone in your office whose presentation skills you admire. Try and emulate that person. Do you like how s/he cracks a joke at the beginning? Or how s/he seems so confident and relaxed? You can learn from them when they're speaking during meetings or pitching an idea. You could also go to them and ask them to give you some helpful tips.
Be succinct
Keep your presentation to the point. Long, windy presentations will bore everyone. Stay within 10 slides. Check your timing. Use visual aids, like pictures, graphs, and diagrams, but don't overdo it.
Body language
Work on how you present yourself in front of your audience. The basic but important things to remember are to stand with your back straight and without swaying, and to maintain eye contact. You can also make appropriate hand gestures while speaking to accentuate your speech. Try to speak in varied tones (change your tone, pitch and volume) so that you don't put your audience to sleep. Project confidence; your heartbeats are quick, you have sweaty palms, you could be trembling, but no one else needs to know this.
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