After you install the App, you will need to enter your email address and accept the terms of service. If you have already created an AUSA Mobile App account associated with that email, you will be prompted to log in.
If you are accessing the app through your browser, you will need to log in to your AUSA Mobile Account.
If you don't already have an AUSA Mobile Account, you will need to sign up for one. You can do this by clicking the 'Meant to Sign Up?' link under the login form.