1. Don't make it obvious that the video is a commercial or intended for commercial gains:
In this video Kobe says nothing about how the shoes help him to jump over a car, or what brand of shoes he is wearing, but yet the viewer is left with the impression that the new Kobe Nike's are going to make you jump higher. Maybe even so high, you'll be able to jump over a speeding car.
2. Video something remarkable:
In this case it was a video of Kobe jumping over a car. Not just any car, but an Aston Martin.
The easiest ways to film something remarkable is to make it either: funny, beyond belief, or entertaining.
In this case they chose to go the beyond belief route, and used special effects to make it appear that he is jumping over a car. It is important to note that the ultimate achievement of a "beyond belief" video is to make it as unbelievable as possible while still making people thing it is real.
3. Use someone famous:
This famous person does not have to be a superstar like Kobe Bryant. Targeting a smaller niche as your demographic is more appropriate for smaller brands. For instance if you were targeting college students in Washington state, you may create a video of the University of Washington's football Quarterback doing something funny.
4. Create a movement:
In this video Kobe jumps over a car and yet encourages people to "not try this at home". But everyone knows that by the end of the weekend there will be 100 YouTube videos of people trying to jump over a car - with most failing I imagine. I really hope we won't be seeing anyone getting hurt.
5. Keep production quality low:
Going back to point 1, viral videos typically do not spread as well if they are commercial in nature. In Kobe's video he goes through the extra effort to adjust the camera at the beginning of the clip to make it seem like he was using a basic camcorder and was responsible for filming the clip himself; really a comical implication.
Low production quality has the added benefit of making the unbelievable seem real. People don't assume CGI work was done on video shot at such low quality.
(When I first posted this blog post the Kobe video was at 38,000 views and had been live for one day. I bet it will go viral and hit over 1 million views in the next week or two. What is your guess?)