From here ..
http://www.nexusmods.com/oblivion/mods/35230/?tab=2&navtag=http%3A%2F%2Fwww.nexusmods.com%2Foblivion%2Fajax%2Fmodfiles%2F%3Fid%3D35230&pUp=1
.. Grab the Main files - For DaRnUI You only need the "WBPG - Installers Creation pdf" and "Wrye Bash INI Tweaks for DarkUI DarN Bain creation"
Use 7zip to extract the "WBPG - Installers Creation pdf"
And put the other zip in your Bash Installers folder
Load up the installers Creation pdf and follow it through ( well, the second half of that guide is for DaRNUI, the first part is for UOP )
Once you have made the DarNUI Bain, its as easy as pie afterwards, and you learn a lot about making your own installers to boot which is the biggest value of that project.
If you have not looked at them before though I would recommend you go through the first two pdf first ( "Basics and Installers Intro" and "Installers Advanced" ) .. Those guides were put together in sequence deliberately to ensure everyone following it was on the same page in understanding everything they were trying to achieve.
At bevilex : O_o people still use buggy old OBMM ?, I would at least use OBMMex out of the two, and even then it is occasionally prone to losing track of some installed files. Wrye Bash is a lot more dependable in the granular control of loose file installations, and you still need it for a Bashed Patch ..imho why bother with OBMM at all ?.