Need help changing the background

[wallet]

Hello, 
I am currently using this theme on my mybb forum.
How can I change the background to an image also is there a way to set the header to an image and have buttons on it?

I really appreciate any help you can provide.

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Also how can I I add a new custom page?

Background is an image,just make sure the image you want is renamed to and the same size of fsbg1.png in images/flipside folder in ftp!!

As in header where screenshot please?