Well, first go to the flag must fall and start the mission.Go out the building that you started at. Go up the hill outside, then go into the trench on the left until you reach a hill. Go right, clear out the pillbox, then get out of the pillbox and go straight. Clear the next pillbox. Go back out of the trench and turn right. There will be another trench here. Do not go into it yet. Pass it, go right, and go downhill into another trench. There should be a path leading left as you enter the trench. Follow it and you will find the MG42, which is a machine gun that you can carry that is just like the stationary guns that were shooting you earlier. Then go reek havoc!