Smartcast is a setting you can do (look in your key binding setup in-game) that allows you to cast a skillshot using your cursor to determine where the shot goes instead of having to hit the button then click where you want it to go. It can save up to like 2-4 seconds.
My friend showed me how to use Smartcast. I thought it was really ugly because you wouldn't know the range of your skills and miss every skill shot when you're using Ezreal, Lee Sin, or Lux.
As time passed, I noticed I was casting spells really slow, so I tried it. It was really hard at first but if you really practice you will get the hang of it.You can do combos faster and actually be a better League player.
