Question

Would you let me know the full form of "Way to go!"

Answer 1

I'd guess it started from something like this: "That's the way to go!" Then it just became shortened.

Answer 2

This is an idiom and idioms are the hardest part of a language to learn. Sometimes this is shortened even more to just,"No way!" or "Way!" These two really short phrases are short for "There is no way that can happen" and "Yes, there is a way it can happen."