The desktop design tool supports two deployment scenarios:
You can work from a blank slate
You can work from a node that already has containers and channels in it
When you work on a blank slate, the distinguished node (DN) must have the desktop service already assigned to it. Once a new node is created and the desktop service is assigned to it, you can then select the new node from the Portal Server management console and click on the Desktop Design Tool link. A tab named Untitled is created automatically in this node and you can start working on this tab.