Once you have created and saved a task, it is your choice when you want to run it:
you can run the task immediately: right after saving that task, Titan Backup asks you if you want to run the backup task.
you can manually run any task at any time: from the main Titan Backup window click My Tasks icon and from the list of your saved tasks choose the desired task and click Start Backup or Start Sync button.
you can also choose to automatically run your tasks - this way your presence in front of the computer is not required. To do this you need to schedule your tasks.