1.First sign up here or here.
2.After that upload the mp3 song that you want on the site that I mentioned for you to sign up above.Where to download mp3 songs? 4shared,aimini.net ahh you can google it.
3.Copy the player's code below and paste in the notepad:
4.Go back to the site where you uploaded the mp3 get the file's Direct Url.The link must end in .mp3
5.Copy the direct link of the mp3.
6.After copying the mp3's direct link go Find the word MP3 URL HERE in the players code and delete and replace it with the mp3's direct link or url.
7.Copy all the code and paste in the INFO box. thats beside the THEME menu on the customize page.
8.It should play if you followed the instructions right:)