You can create and edit automation data directly in the Audio Track Editor. For information about using Automation, see Automation overview.
Click the Show/Hide Automation button 
in the Audio Track Editor menu bar.
An Automation button, an Automation Parameter pop-up menu, and an Automation Mode pop-up menu appear at the bottom of the Audio Track Editor inspector. The colors of the text and background of the selected Automation Mode pop-up menu item display the current state of automation and if there is automation data present:
White text on a gray background = automation is off
Dark green text on a gray background = automation is on but there is no existing automation data to display
Bright green text on a green background = automation is on and there is existing automation data to display
Any existing automation is displayed in the Automation Lane under the main editor window.