Meanwhile, high on the mountain's summit, the sacrificial platforms would be under construction and the burial site being prepared. The platforms were large retaining walls built of stone that formed a large tomb-like interior. The child would be placed within the platform along with many burial artifacts, like carvings of llamas, statues made of gold and silver, and ceremonial pots.

On the day of the sacrifice, the child would be fed chicha, a maize alcohol, presumably to ease the pain of the cold, the altitude, and perhaps the fear of dying. Much ritual celebrating would take place at the platform as the child would be wrapped in ceremonial clothing, placed inside the tomb, and surrounded with the sacred artifacts that would accompany him/her into the Other World. This was the ultimate sacrifice the Inca could make to please the mountain gods: to offer up their own children in the highest places humans could possibly reach.

Whether the children died a violent death remains a debate among scientists. Skull fractures have been found on most of the sacrificial mummies. Johan Reinhard, who admits Juanita, too, has a skull fracture on the back of her head, believes this was a quick and painless means of knocking the children out so that they wouldn't have to suffer a long and grueling death of exposure to the elements. He believes the children were knocked out with a blow to a cushioning towel on the backs of their heads.

Once the child died of exposure, the priests would continue to return to the site, making offerings of coca leaves and filling in the burial site with dirt. Often a miniature figurine of the child would be placed on the surface near the burial site, along with more simple offerings like ichu, wild grass from the slopes thousands of feet below. For Jose Antonio Chavez and Johan Reinhard, these are often the first clues they look for in their search for sacrificial Inca children buried on the frozen mountain tops of the Andes.