fer the rocker cover bolts , you need to apply common sense to tightening them. most talk wench dint go that low and unless your a profeessional or reet keen armchewer you can't really justify the cost of one.
so use a short rachet and socket, if you don't have a short rachet then do not hold yer rat**** at the end because its reet easy to apply to much oomphs and snap the bolts..
now nip em up evenly and once they are all nipped up, you then have to judge how far to tighten them, which is something not easily to describe over the internet.
just use yer noggin, they are only small bolts/nut so don't over do it. if you do get a slight leak just nip em up a bit more.