How to put "Banner" in my mylot layout?

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I saw some of people profiel in Mylot can put extra Banner (example banner Yuwie, banner Clix Sense, etc) How you do that? I've been trying couple times in my Mylot layout, but it not work ^_^;; because i don't know how it works...LOL.. Can you explain to me? And how to change to background of your Mylot layout with other picture??? Thanks for your time.