Backing Up Your Blogger TemplateJust go into the Blogger main menu for your specific blog and choose the 'Template' option. Up in the far right corner is the 'Backup/Restore' option for your template. Just click on that to start the backup process:
A pop-up dialog will appear with the Backup / Restore options with the button to 'Download full template' like this:
The template is just an XML file - you'll see a long, odd name for it when you press the button such as this one:
Just choose a convenient location on your hard drive by selecting 'Save File' so that you can retrieve it later if necessary.
Restoring Your Blogger TemplateIf you want to restore a template, just follow the same steps but choose the 'Browse' option in the window below to find your Blogger template XML file:
You can see that I've selected it - just double-click the file to get it into the file box: