Here's my time tested technique to make sure a head gasket stays fixed: First, to make sure the engine block surface is clean, I use the side of a 6" 80 grit bench grinding wheel [with the paper label removed], spraying the block surface with carb spray, and running the flat side of the grinding wheel over the surface. Keep the surface wet with the spray as you run the wheel over the entire surface. This takes off all the old gasket and leaves a clean surface. Next, run a tap all the way to the bottom of each hole in the block. Then, stick the straw of the can of carb cleaner into each hole, and spray liberally. Next, blast the holes with compressed air till they're clean and dry. Take all your head bolts and clean the threads with a wire wheel. You want to lube the threads of the head bolts with oil, but not so much that they hydraulic lock in the holes. I don't trust click-stop torque wrenches for accuracy, so I've always used the old-fashioned kind that bend and have a pointer. I bring the bolts up to torque spec in three steps, going around in the pattern in your manual. Using modern no-retorque headgaskets, I don't do a re-torque, but you can suit yourself.