first you need a proper instance. the instance must have the opera event defeated. fortunately, alot of bad guilds can clear this, but die to curator/aran/etc. ill leave this up to you, but find a team who has defeated opera, and not defeated chess. by whatever means necesscary, invite them to your group, convert to raid, promote them, and enter kara. then you can leave group.
enter the back door, and follow this video to do the rest.
here is how to prevent aggro from the mobs: download netlimiter. when you want to get buy, set the upsteam for wow to 2 bytes/sec. leave the downstream untouched. when changing to lag mode, wait 5-10 secs before you start moving.
this is not a guide so much as letting you know it still works. you need to be really hardcore to do this properly.
goodluck, got my resto boots and didnt get banned ;p