Assigning a key to a macro

Before you can assign a key combination to a macro, you must create a macro, either by clicking Actions > Record Macro or by importing a macro using the Macro Editor.
Click on Edit > Preferences > Keyboard to access the Key Remapping facility.
Use the pull-down menu to select the Macro category. (If the Macro category does not appear, cancel out of the Key Remapping facility and wait a few moments for the Key Remapping facility to be notified of the macro change.)
Once you have selected the Macro category, your macro should appear in the list in the table, and you can assign a key combination to it the same way that you assign key combinations to other functions.