Idolmaster 2 Demo

[Masterflower]

I need help guys. In the demo, you get to choose what you wanna do on the map screen. There is one that is cost about 4000 credits or money, blah blah, on the performance segment, you get 3 options (Vocal, Visual, Dance) when they are on stage. I don't really understand this part. Do you choose whatever you want to press or is there a key element that I am missing? Please help me lol

[Masterflower]

I did try it, twice and failed twice XD. But I was gifted with a retry on second attempt and cleared it while still not knowing what to do lol. Only thing I noticed was I got a high score this time then last time. Still want to know the point to it lol.