How to Spot

I’ve never read this being discussed so i’d just like to ask people their views and how they think a certain exercise should be spotted. I need to know due to the fact that i don’t want to be to blame if i let a 200kg barbell crush a friend and it would be a whole lot safer if i actually knew how to spot as opposed to pointlessly stand next to the bar as if my extended arms are really going to stop my partner’s max bench compacting his adam’s apple into his nape and so on…

In a 200 kg lift you should be three,one at the middle and one at each end of the barbell.You won’t be able to stop 200 descending fast on your friend if he misses the lift badly.