How do I create timed attacks?

I'm trying to make a game with a battle system like Paper Mario/Mario and Luigi where the player has to time their attacks to deal max damage, if you timed it right the player would deal an "AWESOME!!" hit, close but not just right would net a "Sweet!" and mistiming would usually get a "Alright".

Do any of you guys know how I can do that?

Here is a quick video walk through for you. Let me know if you need anything else!

youtu.be/zIp-limn90I