Become familiar with the wizards, toolbox, and tasks in the ISA Server Management console.
Consider deploying ISA Server 2004 as an additional security layer to an existing firewall environment, particularily where a strong investment currently exists.
Consider the use of an ISA Server Hardware solution that provides pre-built and pre-secured ISA solutions.
Where possible, take advantage of the enhanced caching capabilities of ISA Server 2004, which are turned off by default.
Secure Outlook Web Access (OWA) by using ISA reverse proxy and forms-based authentication whenever possible.
Consider deploying the Enterprise version of ISA Server 2004 if more than two ISA servers will be deployed or if there are advanced design considerations.
Deploy ISA Server 2004 on the latest Windows and ISA service packs.
Consider the use of third-party add-ins for ISA Server that can enable advanced intrusion detection, web content filtering, improved VPN support, and much more.
Document and back up the ISA Server 2004 configuration often to ensure quick recovery in Disaster Recovery scenarios.