[vB4] How could I add my custom header to vBulletin?

[Felix :D]

Hello there,
I am trying to make this my forums new header/background: http://www.gentlemannsestate.com/homeback.htm (Just a demo).
(I also want to use my custom footer)
But this is the out come: http://www.gentlemannsestate.com/forums/

Any ideas or ways you may know of so I can add my custom header in without it screwing with the vB CSS, and making it look nicer?
It looks really screwed up, lol.

Thanks for your time,
-Felix

[webmastersun]

Go header and footer template in your style and making any changes you want.
also you can see my forum http://www.webmastersun.com as references
I made more changes on its footer and header.

[atmoseng]

I am at a loss with customizing my header styles.

When I upload an image URL in the replacement variable for header background > background image, nothing shows up but whitespace. There MUST be a way to customize header with a background image other than the logo image option we are given. Help?

-Mariah