Find head height with your scope (because every character is exactly the same height) then when you spot someone drag your aim towards them quickly whilst keeping it at head height, as it passes over or even gets close to their head, pull the trigger and the aim assist will kick in and do the work for you Best way to snipe in this game because if you have a sniper with high aim assist you really don't need to be amazingly accurate [spoiler]this is called drag scoping and is scrubby, but I do it anyway cause idgaf[/spoiler]