Parrying tips?

What is the timing for parrying? because it seems like I visually block the attack way after I start holding G.

Best thing to do is to also listen for the sound effects, and keep in mind that some attacks can be auto-parried such as light surge but slow attacks such as metal surge require individual parries. Blocking dosen’t have much of a start up time, but does have endlag. Ping also accounts for how well you can parry early game when you haven’t learned to do it consistently.