It can be helpful to do some physical exercise a little while before giving a talk. This wakes up your body, releases tension, and gets the creative juices flowing. 
You can also listen to music that inspires or excites you. And then, just before you're ready to go on stage, try to do some breathing exercises or meditation to calm your heart rate and help you focus.

Exercise, music and meditation

When trying to explain complex information to an audience, the first task is to get the content of what you're saying right. 
How we communicate is also crucial. When someone is speaking, most of the information we receive comes through their body language, enthusiasm and tone of voice. It's our overall experience of the speaker that counts.

What you say, and how you say it

Try not to use technical language. If you do, make sure it is absolutely necessary in order to help the audience understand or appreciate your point – and ensure that you explain the word or term immediately afterwards. 
Keep your words as simple and clear as possible, and use real-life examples and illustrations where possible. But don’t patronize your audience.

How much technical detail to include

If you look alert but relaxed, your audience will mirror this and feel the same way. Stand up straight, but relax any tension or stiffness in your body. 
It’s a good idea to gesture with your hands in such a way that helps to make clear what you are explaining – but only do this if it feels natural, and try not to wave your arms around unnecessarily.

How to use body language

Pacing or moving around as you talk can sometimes add to the excitement of the story, but it can also be distracting. 
It is a good idea to video yourself to see if there are any things you are doing that are distracting or give away your nerves. Fidgeting, fiddling, shifting your weight, swaying or playing with a pen are classic examples of this.

Watch out for distracting movements

One of the most important areas of body language is eye contact. This can really help an audience feel immersed in the story, but can also help you, as a presenter, to feel less nervous. 
A few seconds of eye contact with individual audience members will actually help to calm your nerves.

Make eye contact with your audience

If you can get an audience to really 'see' what you’re trying to explain, they will not only be able to understand it better, but they will also remember it.
Analogies and metaphors work really well, especially if there are no real-life examples to draw on.

Metaphors and imagery

Think of your talk as a series of self-contained mini-talks, then if one part goes wrong, gets forgotten, or simply doesn’t feel like it’s working on the day, just jump to the next part – you can always go back to it later.

Break your presentation down

Nerves are a perfectly normal phenomenon and are a very useful way of making sure that you are fully energized, revved up, and ready to deliver your talk. 
Embrace the adrenaline rush and try to think of it as excitement rather than fear.

Make adrenaline work in your favour

It is important to celebrate your own uniqueness and use your own way of communicating. 
Think about how you would tell your friends an exciting thing that happened to you today, and what gestures you would naturally use.

Be yourself

Explaining complicated ideas is not always easy. Dr Emily Grossman, an expert in molecular biology, broadcaster and educator, who trains contestants for the FameLab International science communication competition, gives some tips on how to do it. What's more important: what you say, or how you say it?

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