In the application view, click the Tasks tab.
In the navigation pane, click the desired task list . The tasks in the task list you selected appear in the table pane.
Click 
in the
New button, and from the drop-down
menu click Tasks | Single.
In the New Task dialog box, type:
The name of the task
A description of the task (optional)
Type the start date of the task in m/d/yyyy format
or use the date chooser 
to
select the start date.
Type the due date of a task in m/d/yyyy format
or use the date chooser to
select the due date.
Click 
to create a dependent task.
In the Choose Dependent Task dialog box, select one or more prerequisite
tasks, then click Finish.
Select This task is a milestone if you want to identify the task as having a single date of an important occurrence or turning point related to a project.
Select the Display in Calendar if you want the task to display in the calendar.
Click 
if you want to assign a task
or change the assignment of a task. In the Choose Users dialog box, select
the users to whom you want to assign the task, then click Finish.
As an optional step, in the Status
area, you can type a percentage (between 0 and 100) to indicate the portion
of the task that is completed. Also select the risk indicator that
best represents the risk status of the task: 
(green) no
risk, 
(yellow) moderate risk, and 
(red)
high risk.
As an optional step, in the Notification area, you can select when project members should be notified about new tasks that are added to this Task List.