To add a copyright statement to the footer of every page, you'll need to use the advanced customisation tool which is available on the Business plan and above. This tool will give you access to the code which is available to see within the Design section of your SupaDupa admin.
To add your copyright statement, simply go ahead and:
Log into your SupaDupa admin
Click on the Design tab
Click on the spanner tool seen on the left hand side of the page. See below:
Turn off the 'use filler content' toggle so it becomes grey and choose the 'theme' template.
Now that you have selected the theme template, the code for this template will appear in the middle of the page.
From here, scroll down to the very bottom where you'll see </div><!-- end footer -->
Directly above </div><!-- end footer --> simply add your copyright statement.
Please note, it will need to include HTML tags so it may look something like this.
<p class="copyright">Copyright © 2015 SupaDupa Me Ltd. All Rights Reserved.</p>
That's it - you're done.