First of all, I would encourage that you post the MP3 to as many services as possible and send the link throughout all of your social media platforms. Choose links that best fit the methodology of the site upon which you will be promoting. For example, embedded links work best on timeline-based platforms like Facebook and Twitter. There is something to be said about being able to play the MP3 without having to visit another page. This can also be done by uploading the song to YouTube with some kind of place-holding graphic like an album cover and a web link as the visual data.
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