Hey Man! do you have the international versione of One? if yes you can follow these easy steps.
Before start doing s.off you MUST unlock you bootloader, see this thread http://xdaforums.com/showthread.php?t=2183942 . this kit is very user friendly .... ste 1 you download drivers, and etc etc ...follow the 5 steps in the upper left part of the toolkit.
Once you have unloked the bootloader, you can start with s.off, i suggest you use the revone method http://xdaforums.com/showthread.php?t=2314582
that's all. do you need also to change CID ?
Thank you.. That did the trick.. For some reason I though you have to go back to stock before you can get s-off. But that is not the case!