People get a little too anal taking the head off in steps IMO. I use an air gun and zip the bolts out starting from the outside and working toward the middle - alternating sides. When installing the head just start in the middle and work in a spiral pattern out towards the ends of the head. It is best to torque it down in steps but just be sure you use staps that are no smaller than 15ft-lb increments as it can easily take over 10-15ft-lb to get the bolt started turning once it starts to get tight and you can end up with a false torque reading.