When the app starts, press to move over to ‘Library’ and select ‘Interactive Episodes’.
This is first unlocked in Episode 3, ‘Goodbye Pacifier’, Chapter 1, ‘Make Shapes with Abby’.
Throughout this chapter, Abby will be styling hair for three dogs (and herself). Each will have a shape (square, circle and octagon). When Abby tells you to, just wave your hand back and forth with the Kinect. You have to do this three times.
You get other chances to unlock this achievement in Episode 5, ‘Humpty's Big Break’, Chapter 1 and Episode 7, ‘Rocco's Boat’, Chapter 1.
The simplest way to unlock this achievement is using ‘Chapter Select’ to choose the chapter. When the chapter is over and the next one starts, just press , move over to ‘Stop’ and press again. The achievement will unlock when it is buffering. You can alternatively watch the entire episode, but that would be more time consuming.