You can map keys on your computer keyboard to toggle software buttons on and off in Live. When key mapping, it is best to disable the computer piano keyboard to prevent conflicts by clicking its icon in the upper right area of the screen.
Once the computer piano keyboard is disabled, press the key mapping button (also located in the upper right area of the screen). You can then click on almost any parameter in Live to select it for key mapping. Press and release your desired computer key once, then click the key mapping button again to exit key mapping mode. You can now press the mapped computer key to toggle on and off the mapped parameter.