Save the music you want to copyright on your hard drive in MP3 format.
Go to the United States Copyright Office website (copyright.gov) and click on the "Electronic Copyright Office" icon or the "eCO Login" button. Continue on to the Electronic Copyright Office.
Register for a user account, if you have not done so already, and log in to the Electronic Copyright Office.
Start a new claim. Choose "Performing Arts" as the "Type of Work" you want to register. Enter as much information as you can on the nature of your copyright, such as the author, the year the music was created, contact information, etc.
Submit the required application fee using your credit card. As of 2010, the online application fee for a performing arts application is $35.
Upload the MP3 file(s) of the music you want to copyright online.