This HOWTO will provide some basic steps toward hardening your Freshtomato router. It is not intended to be a thorough or complete reference on securing your network. It is only a starting point.
Each small step will reduce your network's attack surface.
Go to the Adblock menu and enable this feature. If not completed already, add Domain blacklist URLs from the wiki list to choose which content to filter.
In the Routing menu, disable “Accept DHCP Classless Routes” (option 121). This will reduce exposure to attacks from rogue DHCP servers sending malicious/fake routes.