override AFTER changing orignal templates

Ok. So I've done the unthinkable.

I've made most of my changes on the default template on a test shopping cart, which is ready for showtime.
I'm on godaddy. How can I remedy this (i.e. create override) before taking the shopping cart live? Apologies if this is clearly posted somewhere. I see all the help to do the override, but I cannot make the link to the obvious, how to override after you've done your changes? Is that even possible?

If you know what files you changed (or can locate them), you can create folders for them and copy them over.

For example, let's say you modified includes/languages/english.php. Create a folder for your template under includes/languages (we'll call it YOUR_TEMPLATE for now). So you'd create a YOUR_TEMPLATE folder under includes/languages and copy english.php into it. You'd end up with includes/languages/YOUR_TEMPLATE/english.php.

Anywhere you see a /classic/ folder, you can create a folder for your custom template. You can copy the necessary files from either the /classic/ folder, the /template_default/ folder or the parent folder.

Edit includes/templates/YOUR_TEMPLATE/template_info.php to give your template identifying information so you'll recognize it in the admin under tools->template selection.

When you're done, don't forget to reset the sideboxes.

And schoolboy gives an excellent tutorial in this thread on how to go about setting up your custom template:

http://www.zen-cart.com/forum/showthread.php?t=135481

Thank you, both. I will work on this carefully. Super helpful!