Once users are able to authenticate to your GitHub Enterprise instance, they'll want to set up a few basic custom profile settings like an avatar and email notifications.
Site administrators can promote any normal user account to a site administrator, as well as demote other site administrators to regular users.
To make it easy for users to respond quickly to activity on GitHub Enterprise, you can configure your instance to send email notifications on issue, pull request, and commit comments, as well as additional settings to allow inbound email replies. Notification emails are sent if there is activity on a repository a user is watching, if there is activity in a pull request or issue they are participating in, or if the user or team they're a member of are @mentioned in a comment.
You can create a custom message that users will see on the sign in page.