I do something like macropod said.
Instead of saving in normal.dotm, I save my macros in the MYMACROS.DOTM file and save and keep in the word initialization folder (Options - Advanced - General - File Locations).
Easy to back up and restore. (No need to export/import modules, userforms, etc.).
Note that, in order to gain access to the code, you must open the file from the File - Open menu.
For backup and easy reference to the code, I also save each individual module / user to a folder.

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Backup your original file before doing any modification.