Or try Control. The game lasts longer so you have more time to get headshots. And the opposing team will always be heading to 1 of 3 zones. Just lurk outside radar edge and ambush. I'd use grenades or smoke to lower health then hope the last shot was precise. It took me about 15 matches before I got it. Oh and play during off periods - before school lets out, not on weekends, etc. It's hard to compete with 15 year old hand eye coordination.