There are two methods for selecting tasks for a trigger.

Step 1	Click the Add-Remove Multiple icon next to the Tasks(s) field
Step 2	Select one or more tasks from the Edit Members pop-up dialog:

In addition to the previous method of selecting task(s), you can select a single task by

Click the drop-down list arrow next to the empty field that displays below the Task(s) field and select a single task from the list of all tasks.
Begin entering a task name in the empty field; the user interface will auto-complete the name or display a list of names that match your entry.

When you have selected a task, it displays in the Task(s) field. You then can select another field.

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