Should:

Research and understand the target audience,
Be creative, do not be constrained in thinking. Trademarks can only be secondary, priority is engaging and brings entertainment value to consumers.
Encourage conversation and dialogue. YouTube is a social network and the communication is so important. In some cases the story is between brands and consumers, but most are still shared between consumers together.
Be prepared for positive stories and negative brand around. In fact, people have many opinions and everything depends on the brand's driving the different points of the star.
Be generous. Do not expect to receive anything from the YouTube community. The main function of the YouTube community is to create brand loyalty. You will not achieve this by trying to sell more products to them. However, you may succeed to bring compelling content, innovative and useful to them.
Do not:

Using the content used. YouTube thrive originality and creativity.
YouTube assumptions can replace other forms of advertising. Social networks should be used to amplify the brand message and build more from the fruits gained from other channels.
Trying to distort, manipulate feedback or stories online. Nothing can ruin the brand by posing as consumers.
Assuming all the clips on YouTube will spread. Try new things, learn and try again.

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Yepi , juegos