The common mistake people make when devising their own videoscript for the first time is failing to recognise that it is for watching and listening, and not for reading. These tips might help.
1. Break down your content into simple sentences.
2. Relax somewhere, pick up your phone and pretend you are telling a friend about the points you have chosen. 
3. Write and learn your script in that same conversational style.
4. Read you script out loud to a colleague preferably, until you completely at home with it, before you go to camera.
4. Remember you are going to show, not tell, so include as many cutaway shots of your subject matter as you can.

You would be surprised how many people appear before a film crew and haven't even devised their script, let alone learnt it!

1.You will attract people to your stand and keep them there longer.
2.Visitors are more likely to remember your offering and your branding. (see previous blog)
3. Some people want to learn more before they engage with you.
4. A pre-planned film will show your business in the best light and important points will not be missed.
5. You will have a perfect ice-breaker!
6. You can use versions of the video on social media to prepare and attract visitors beforehand, and afterwards to reinforce your message.

Edgar Dale's research led him to create his 'Cone of Learning', showing a hierarchy of how much people could remember related to different methods of delivery.

After two weeks, it suggests that we tend to remember just 10% of what we read, 20% of what we hear and 30% of what we see.

Interestingly, retention rises to 50% if the learner can both hear and see the information (which at least potentially puts video ahead of audio!).