Step 1. In your Shop administration go to 'webite' >> 'Design Manager'
Step 2. Click 'Custom' tab and select "Page" from "section" dropdowns
Step 3. To upload your own page background image, click on the ?Upload image? button under 'Page background image' and it will show a popup
Step 4. Click 'Choose File' button to browse your own background image file and then click 'Upload' button.
Step 5. Adjust the 'size' and 'repeat' settings according to your preference.
Step 6. You can preview the image in layout manager
Step 7. Click 'Save' and then click 'Ok' button
Step 8. Now go to your website and refresh the page to view the new background image.
For more information about how to use Design Manager to change the look of your site, you can also refer to our VPCart 9 User Guide at
https://helpnotes.vpcart.com/userguide900/#!Documents/howtousethisdesignmanagerfeatureinvpcart.htm