WHEN DESIGNING YOUR WEBSITE, THERE ARE SEVERAL THINGS YOU CAN DO TO MAKE THEM STAND OUT.
To breakup the apps on your page, you have the option to turn on the App Titles.
With the App open for editing, click App Options in the upper right.
First give your App a goood descriptive name. Then click "Show the app name on my page" to display it.
When editing your pages click the "layout" tab and select a page layout. You can then drag and drop new apps into one of the layout regions. if you change an exisiting page's layout you can drag and drop exisiting apps to different regions.
Can I put a background image on my page? Yes. Should I put a background image on my page? Probably not.
Blackboard does allow you to add a Background image to your pages. It's under the Page Options.
However, the image needs to be a very high quality image. It needs to be a very large image to take up as much space as possible before it starts tiling. And it has to look good tiled. That is not easy to do. Also the image will only cover the main content area. Not the header, not the footer, not the left navigation.
You can see an example of a background image being used on my sample teaher site. https://www.d11.org/Crosbie. Notice this page is not a very long page. As the page gets longer the image will end and then repeat. this is where page can start looking bad.
Additionally, the image needs to be light enough so that you can read the text on top of it
Bottom line - my recommendation, it's not worth it.