I know most musicians are confused about copyrighting their music. I’ve done it before by following these guidelines. Everything you need to know and do is in this article or the links contained in the article. It’s not that difficult. Just follow this guide from the copyright office:

Performing Art Works

Follow these steps to register your musical work, dramatic work, script, pantomime, choreography, motion picture, or other audiovisual work:

Step 1

Make sure your work is a performing arts work. Performing arts works are intended to be “performed” directly before an audience or indirectly “by means of any device or process.” Included are (1) musical works, including any accompanying words; (2) dramatic works, such as scripts, including any accompanying music; (3) pantomimes and choreographic works; and (4) motion pictures and other audiovisual works. Note: Performing arts registration is not the same as registering a sound recording. Read more about choosing the correct registration method. To register sound recordings, see the Sound Recordings instructions. Read more about the registration of musical compositions and sound recordings.

Step 2

Put into one envelope or package:

a completed application Form PA or Short Form PA and Form CON if needed (choose which form to use).
a $45 payment to “Register of Copyrights.”
nonreturnable copy(ies) of the material to be registered. (Read details on deposit requirements for musical compositions, motion pictures.

Please read this important notice about mail delivery disruption.

Step 3

Send the package to: Library of Congress
Copyright Office
101 Independence Avenue, S.E.
Washington, D.C. 20559-6000 Your registration becomes effective on the day that the Copyright Office receives your application, payment, and copy(ies) in acceptable form. If your submission is in order, you will receive a certificate of registration in approximately 6 months. For more details, please see Circular 45, Copyright Registration for Motions Pictures Including Video Recordings; Circular 50, Copyright Registration for Musical Compositions; Circular 55, Copyright Registration for Multimedia Works; and other informational circulars. The Copyright Office is changing the format of certain copyright registration certificates, as part of a pilot project that involves registrations for motion pictures and other audiovisual works. (read more)

Notice: Please be aware that when you register your claim to a copyright in a work with the U.S. Copyright Office, you are making a public record. All the information you provide on your copyright registration is available to the public and will be available on the Internet.