unless I missed somthing these adjustment hints seem to assume he has a solid lifter cam?
if it's hydruallic lifters, I prefer to adjust them with the engine running.. it seems to give me less trouble (I've wiped out 2 cams in the past trying to do them with the engine off)
warm the engine up, shut it down, take the valve cover off, restart the engine (it will be flinging oil everywhere, so work fast)
one rocker at a time, back it off until it taps, then tighten it back up slowly until it stops tapping, and then 1/4 turn more.
then put that valve cover back and do the other side...
I made a tool to help control the mess, I took an old chrome valve cover, and cut a small window in the top of it to give me easy access to rocker nuts, but keep most of the oil inside the engine.
the window needs to be offset to the 'top' of the valve cover as it is installed on the engine.