[WillyK007]

well this is first player mode so you dont even have to get online

the yellow arrow is where your teammate should be

NOTE: make sure that you CANNOT see inside the red, circled area. or else the bodies pile up and your guy will stop shooting at the turret man (he cant see through the bodies.

you get anywhere from 3500xp-5500xp per hour using this method, clearly when you are doing it you get more xp