Hone your craft. Enroll immediately in singing and acting classes. Miley Cyrus and Britney Spears have shined as both actresses and singers on the station. They didn't get that way overnight. Miley was exposed to music her whole life, and Britney had been in dance classes and auditioning--on shows such as "Star Search"--for years. The best chances for success will be granted to those who are talented and polished in their performing abilities.
Submit your headshot and resume to all the current shows that are casting on the Disney Channel. Do a separate submission for each show. The address for the Disney Channel is: Disney Channel, 3800 W Alameda Avenue, Burbank, CA 91505. Although that is the address for the channel, some shows are shot on location, while others have homes at other addresses. Double check with the guide and agent before submitting yourself for each show.
Find an agent. The best way to secure Disney Channel auditions is through an agent. You can inform the agent of your specific desire for landing Disney Channel singing and acting parts. You'll find the link to the Screen Actor's Guild search tool to find a legitimate agent in any state in the country.
Consider being an extra in a Disney Channel series. Several current shows are seeking background performers for the show. If you are interested in getting a glimpse of life on the set, submit your headshot and resume for extras casting to: Central Casting, 220 S. Flower Street, Burbank, CA 91502. While this is not exactly acting, some people have been bumped up to speaking parts when working as background performers. Be on your best behavior and shine as an extra to be noticed. If you have questions on current shows casting, call Central Casting at 1-818-562-2755.
Be flexible. Don't choose roles that only include both acting and singing. Performers have long been able to switch gears between acting and singing if they're equally talented at each. Just because you take a non-singing role, it doesn't mean that you can never combine the two in your career. Seize all the opportunities you can.