How to write a cover letter for oDesk

Example:

I am an expert of media marketing. I will do marketing by:
Social media like, facebook (fan page and groups), linkedin, twiends etc.
Bookmarking like digg, delicious etc.
Commenting on blogs and forums.
Email marketing.
Youtube marketing.
With my websites and blogger sites and etc.

Marketing strategies of mine will ensure to increase your web traffic. I can do it for 14 hours a week. It will my pleasure if you would give me an opportunity to do.
Thank you