Product reasearch: How to get my message across

I have been thinking about what i want to achieve whilst making this documentary, therefore i need to be successful in getting my message across. i have been looking at various websites and noting what they do to make their documentaries successful.
Here are tips the Film-Street website offer when wanting to putting your message across:

• Interview people In some documentaries the filmmaker is part of the film. He or she may be seen interviewing people and we hear what they think about what is happening.
• Use a voice over or narrator A voice over or narrator can set the scene and give more background information.
• Stay behind the scenes In lots of documentaries we don't see or hear from the filmmaker, but it is important to remember that we are still hearing their version of what happens.

Channel 4 have good advice on narration skills and because i am thinking of including a voiceover, they have useful tips on how to make it good.
1. Never describe what's going on in the pictures
2. Use words that are simple and easy to understand.
3. Keep sentences short.
4. Facts in commentary - leave the emotion for sync.
5. Do not express personal opinions (unless you are a subject of the film).
6. Less is more.

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