There is an AutoCAD user with 20 years experience, migrating to Revit. This user prefers using keyboard shortcuts over icons (Who doesn't?).
* Let's get this out of the way first: Don't press Enter after typing a keyboard shortcut in Revit. Pressing Enter will make Revit redo the last command. Revit is not AutoCAD *
Revit's keyboard shortcuts can be accessed by browsing to the Application Menu > Options > User Interface > Edit (Keyboard Shortcuts). The typical workflow to assign keyboard shortcuts in Revit, is to search for a specific command, and then assign the shortcut in the Keyboard Shortcuts window.
But what if we do not know which commands exist in Revit? This is where an alternative use for the Export command comes into play.
When opening the Keyboard Shortcut XML file, choose that Notepad should be used. The first thing to notice is the Command Name. Secondly, does the command have a Shortcut assigned? It should be noted that these are the only areas that should be changed in the file.
As can be seen from the example below, shortcuts were assigned to the Solid Extrusion, -Blend, - Revolve, -Sweep, and -Swept Blend commands.
When Saving and Importing the modified Keyboard Shortcut file, you will notice that the shortcuts are imported without any errors.
Personally, I prefer to rather add and change the shortcuts from within Revit, but some users, especially those who were on the level of creating AutoCAD .pat files via notepad, might find this method easier and/or quicker.