For ICE installations that allow users to create accounts, there is a Create Account button on the login page. Click on it to navigate to the Account Creation page. Enter your name, email address, institution affiliation and brief information about you. Click Submit to create the account and a temporary password will be emailed to you.
If you get an error message when creating the account, then it is likely that the email address you used already has an account associated with it. In that case, use the Forgot Password feature to reset your password.