Go to your Profile (click the My Profile link at the top right). You will see a music player. On the player there are several buttons. Click the one that looks like a wrench. A new window will open.

Click the browse button to select your song. For most users, you will have to go to your Music Folder, select an album and then a song. Give the song a title in the box that says "File Title."

Give your song Tags (Tags are searchable keywords such as the artist's name, song title, music genre, etc.) and a description.

Hit the upload button and your song will be ready to play! (Note that songs must be approved to show up in your player)

Have fun building your profile!