When you are nervous when giving a presentation there are various things that you can do to reduce the nervous feeling. One of these things is holding something in your hand. This helps to distract your brain and may reduce the nervous feeling.
You can hold a marker or clicker in your hand during your presentation to help reducing the nervous feeling.
Don’t play around with it too much as this may distract your audience. Just hold it (tight) during your presentation and you may experience feeling less nervous as holding something in your hands is a distraction for your brain.
Looking for more tips to reduce the nervous feeling? Have a look at the book that is part of the Public Speaking Kit.