Its a good idea to use a spray copper coat on the intake/ex manifold gasket. If it has a problem with warpage or rough surfaces you can use a high temp copper RTV on the gasket. Tighten the bolts a little at a time from the center out. I like to put grade 8 SAE flat washers under the heads of the bolts to transfer the torque better. After you warm up the engine tighten them again & once more after it has been driven a while. Like 66 says, glue the gasket to the valve cover. Tighten them the same way, a little at a time , keep going around. I like to put a little RTV on the rear edge of the valve cover gasket as that is were they tend to leak.
