Go to the dengbarun (whatever it is) team and when you spawn go to the staircase to you right, go to the edge of the staircase (also on the right) and lay down and go into it. You will be inside the staircase. Note: you cannot shoot out of the staircase when you are in it so when an enemy comes by, stick you head out of the staircase (from the place you entered) and then you can shoot him.