How do people get more efficient at getting headshots? And how do they know (roughly or precisely) at what hight to aim in order to maximise the chance of getting headshots? I've been trying to use objects in the map (which I've read is how...

I've been wanting to put a team together a team for the upcoming premier league but unfortunately it's only myself and a friend... both gold players that play flex... and quite possibly might have too many agents in the pool for competitive...