Sweet, ok. Um so first you go to the homepage or "my mibba" which is up the top of the page.
Then on the right hand side, theres like topics or groups and you find the one that says Profile.
In that group, find where it says CSS and click on it. It should take you to a page with a box filled with codes.
Under that, it has topics which read "info," "colour picker," and "layouts." Click on the link under the heading "layouts."
That should take you to page with a massive choice of pre made layouts. Chose the one you like, preview it if you want and then click on where it says install, which should be right under the picture of the layout.
Hope that helped, I'm not very good at giving instructions. =)
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