http://youtu.be/anfkvlVaImE Start Patrol on earth, and you are already looking at the building. Kill the enemies outside go down the stairs. Wait for them to spawn. If they ever stop spawning you have to go out side and kill the major that comes on the ship. You will hear the ship. Easy bounties, Enjoy everyone.
u don't have to go down stairs just stay at top of stairs next to the rail. also if u have a friend that will help ur friend can stay on top and kill enemies when ship comes and u stay down there for however long yall decide then switch .enemies spawn every 6 sec.....