You cannot change evolution layouts, from being inside standard layout. You must first switch to Evolution, and then you will have the option under the usericon, and can change the Evolution layouts. If you login as admin and then, as admin, login as user, then maybe this setting is missing, then you must login directly as user.What about if you're in the old Standard layout.
Where is the Skin Manager if you want to change it?
I see. "Document Root to Demo Skin" and you can type in 'Evolution'
However that does not change it.