Forget the rest of the incomplete articles you’ve found, just do this.
1) It doesn’t matter if you’ve downloaded a template or made one yourself, just make sure you know where you’ve put it.
2) Usually, the template folder is in: C:UsersYOURUSERNAMEAppDataRoamingMicrosoftTemplates and you can just drop the template file in there. Next time you click on the Office button (circle button, top left of Word window), choose my Templates and voila.
Except you might have been a hero during the installation process and changed the installation paths. Here’s how to find out where your template folder is pointing to:
1) Click Office button, choose New
2) Choose My Templates
4) You can double click on that location and copy it to the clipboard (Ctrl + C)
5) Click on the Start button (windows desktop), choose Run and past in the location. Now drag and drop your template file.
I highly doubt you’ll have questions, but if you can’t manage to do this, please leave a comment so I can make fun of you.