All in all this is a job that is very cheap at a machine shop and probably should be left up to them to perform just because of lack of knowledge but heres the instructions anyway.

Place the cylinder head with the combustion chamber facing up with the intake face away from you. Place a 400 gasket over the deck surface and carefully mark the six holes with a starting punch. The holes on the exhaust side should be drilled straight into the head. The holes on the intake side must be drilled at a 30 degree angle toward the exhaust side. You can use a protractor from wal-mart to help with the 30 angle. The center holes should be 7/16 and the outboard holes should be 3/16.