Mocksup can make your mockups look more like real web pages by giving you the ability to change the background image and color of the page your mockup's displayed on.
You can upload a background image to the entire project or to individual mockups.
Changing a project's background
To change the background of an entire project, go to the project's thumbnail page and click on 'Project settings'.
Next click on the 'Background, color & alignment' tab and you'll see fields for 'Background image' and 'Background color'.
Upload your image, change the background color to match if necessary and then save your changes.
Changing a mockups's background
If one or more of your mockups needs a different background than the rest of the project, go to that mockup's editor page and click the 'Mockup settings' link.
There you can set new values for the 'Background image' and 'Background color' fields.
If a mockup has its own background image or color, it will always show instead of the project's background.