Drag the icons to the empty Sprunki/Character and it plays a sound, click the character to mute then click it again to unmute, there are different types of character settings on the bottom or the singing or beatboxing character if you want to use, like the volume. And if you want to remove the character, just drag them down.
Credits in the game, how to get there: 1. click on more (three lines) 2. click on C 3. here you go
