always start in the middle and then out to the ends doing them diagonaly at each end then start working ur way back into the middle doing the same routine and of course remember to torque them down to the right settings
It's in the Manual - but basically, making sure the stud threads are clean and lightly oiled - start in the middle at the dizzy side then alternate side to side and back and forward - just pulling them down in easy steps evenly - finishing off at 44 ft lbf. Only then - tighten down the 4 rocker pillar nuts to 25 ft lbf. Set inlet gaps to 12 thou and exhausts to 15 thou. Run the engine through a heat cycle and then retorque the head nuts - and reset the valve gaps.