To Attach one Task to Another Task

In the Animation Producer dialog, select the Attach Task to Another icon.

The Attach Task dialog opens.
From the Task option menu, select the task you want to attach to another.
From the Parent option menu, select the task to which you want to attach another task.
Accept the attachment with a data point.
Parent tasks display in black in the graph and are bold in the tree view and Schedule Panel list box. The subtask displays as attached to the selected parent task.