Cloning a Template
If you are looking to do this, your best option is to:
Step 1. Start a new page by clicking Use Template.
Step 2. Choose the template you need and click Use template again.
Step 3. Add in the changes you need.
Step 4. Make sure to rename it so you don't have 2 identically named templates.
Step 5. Head to the page menu and choose Convert to template.
That's it, you've successfully cloned a template! It will now show up as a different template under My Templates.