Well there is no way you can 'optimize' your Facebook profile. However you can do some promoting for your profile if you wish by attempting to do viral marketing campaigns. But I doubt you might get any traffic or help from it. If you mean to promote your fan page, then obviously viral marketing will help you for sure.
I am not sure but is this what you are asking for? http://www.facebook.com/ChangeYourTheme http://apps.facebook.com/ownskin/ These are apps that will change your Facebook theme.
There is no option of changing theme in facebook. All u can do on facebook is share imagies n liking stuff