How to enable iTerm2's system-wide hotkey when iTem2 is not running
Follow these three steps:


Launch Automator from /Applications/Utilities. Create a service for launching iTerm in Automator in these steps:

1.1. In the first window select Service and press Choose.



1.2. From left sidebar select Utilities. From middle section drag Launch Application to the right section and select iTerm from the its dropdown list. Select no input from upper dropdown list. Save the document by command+S and provide a meaningful name like Launch iTerm.





Open System Preferences and open Keyboard section. Navigate to Shortcuts tab. From left sidebar select Services and from right list scroll to General section. In this section should be an item named Launch iTerm. Select it and then click on add shortcut button appeared in the right. Assign a shortcut like control+command+Z.


Open iTerm and navigate to the preferences. Assign the same keyboard shortcut in previous section.




This keyboard shortcut launches iTerm when it is not running and shows/hides iTerm when it is running.