Collect equal notes or notes of the same color the make them harmonize. When a musical symbol falls, you can move it to one of the 5 tubes that are over the houses: when you match 3 notes with the corresponding shape or color, they vanish from the tube and you earn points. Some bonuses can help you on the way: the circle of changing colors allows you to change everything to the same color at the tube where you send it; the treble clef, change everything at the same time inside the falling tube. As you progress in the game it will be more challenging.
When a musical note falls, click in a house so the note goes to the right tube.