To Modify a Function Key Definition

Select Function Keys from File > Settings > User .
The Function Keys dialog opens. The title bar identifies the open function key menu.
Do one of the following:

Select a function key from the list box.

or
In the Function Keys group box, turn on the Ctrl, Alt, and/or Shift check boxes and select the desired function key from the Function Key Drop-Down List.

or
Using the keyboard, press the desired function key and the <Ctrl>, <Alt>, and/or <Shift> keys.
In the Action text box, edit the definition. The definition must be specified as an action string.
If you wish to save the function key menu with a different name or location, click Save As Function Key Menu . The Save Function Key Menu As dialog opens.
To save the function key definitions in the open function key menu, click Save.
The open function key menu is overwritten and the Function Keys Dialog closes.