Educate yourself on copyrights. A copyright is a form of protection for intellectual works, including movies, novels, film and, of course, music. Technically, a work is copyrighted at the moment of its creation. It's generally a smart idea, however, to copyright the work in case someone decides to claim the work as their own. It is important to understand when a copyright is valid, what kinds of works are protected by a copyright and the best method of copyright for the work in question.
Register a copyright for the music. At the time of this writing, there are three ways to copyright your musical work.
The first is online through the electronic Copyright Office (eCO). By making an account, eCO allows you to fill out all of your information securely online, pay using a credit card or direct bank account deposit and upload music in several different formats. This is the preferred method and offers several advantages, like lower registration fees and faster processing times.
The second method is by filling out form CO. This is an online form that can be filled out, printed and mailed in with a hard copy of your musical work on CD.
The third method is through paper forms, specifically Form SR for audio recordings. These can be sent filled in manually and sent in the mail. This is the most expensive of the three methods and nearly twice the rate of the eCO.
Build a website. A website puts your music directly on the web for the world to see. It allows you to publish your music directly to the consumer and build a following. Updating regularly is crucial.
Join freelance sites. Publishing music directly on sites such as Freelancer, Elance, and Odesk puts you in front of hot prospects looking for music.
Become a member of TAXI, a company that solicits to companies and individuals looking for music that they normally wouldn't have access to. They offer solid critiques and have a long list of clients from the likes of Disney, RCA, Dreamworks, and Fox.