Use the 1, 2, 3, and 4 keys to control the buttons with the corresponding numbers. Press the key whenever the falling notes indicate.
The song is "Death by Glamour" from Undertale. I picked it mostly because the bass line only has 4 notes, so it fit well with the 4-key interface. There's only 4 measures of the song, hence the MINI in MINI GUITAR HERO :)
