The online enlistment process will help you get started

This application is used to prequalify individuals for enlistment and provides more complete information to your local recruiter. By simply filling out this application, you will not be committed to enlist. The application, however, will help us determine which jobs suit your abilities. A recruiter will contact you once you release your application to the Army.

 http://www.goarmy.com/learn/apply.html