Stage One has two parts: the Immaculate Heart and the Sacred Heart. We begin with the Immaculate Heart, because Mary leads us to the Sacred Heart of Jesus. We begin our journey to the Immaculate Heart with the book 33 Days to Morning Glory and its accompanying group-retreat program. The goal of this program is to lead us to formally entrust ourselves to Mary. Mary then leads us to the Sacred Heart, which begins the second part of Stage One: the book Consoling the Heart of Jesus and its accompanying group-retreat program on Divine Mercy.
If you have not yet done the 33 Days to Morning Glory Group Retreat, you will want to look into doing that first, as it will make Consoling the Heart of Jesus a more fruitful experience.