Users with email login may reset their password from the sign-in page or via the admin site.
From the sign-in page
If you're not logged in, navigate to the sign-in page and click the link to "Recover your account" button.
This workflow is only available to users with email addresses. Users who log in with their badge can only have their PIN reset by an administrator. See this article for steps to reset an employee's PIN.
While already logged in
If you're already logged in to the admin site, you can change your password by clicking your name in the the upper-left hand corner, then clicking the "Change Password" button.