You may use the main menu option Task -> New Base Task / New Sub Task to create a new base task or a sub task for the currently selected task. Or you can click the New Task button on the toolbar. You can also right click any item in the Tasks list and make the same menu option choices from the tasks tree context menu. A Task Properties dialog is displayed. Enter a Task Name for the new task or sub task. The same Task Properties dialog opens by clicking the "Edit Task" item on the Task menu or the tasks tree context menu. Use it to edit any of currently selected task's properties. Other options available on the Task menu and the tasks tree context menu allow you to "Start this task", mark the task "Complete" or "Closed", or "Delete" the task. To make a task active and start time tracking just double click the required task.