how to change head gasket on ka24

[patch]

ok heres the story: i was in the desert for a while and i let my room mate use my car. well when i came back, the motors about taken apart. he blew the head gasket and tried to replace it himself, and now its up to me to finish it. so far hes got the valve cover and head studds and exhaust and part of the intake manifold off. what else must i do to get the head off? its a single cam.