Its simple :-

I learnt this from the hackintosh community

Boot in -s [Press Apple Key +S]

then type mount -uw /

then run sh /etc/rc <-- the one shown in the how to start system

It will start the system in single mode. Then type this

diskutil repairpermissions /

It will take sometime for it to repair its permission

If it fails , then I suggest you to restore back its permission , we have no choice to do that

to do that

chown -R root:wheel <folder name> then chmod it correctly

Sometimes diskutil does not fix permission and dont even mess with permissions. This is a *nix based system. dont ever........its very dangerous