These early ancestors of the Incas had a totally different approach to mummification. They completely disassemble the body (including the skull), removed all flesh, heat-dried, treated and reassembled it. Sticks were inserted to strengthen the limbs and spinal column. They even packed the body with such neat stuff as feathers, clay, grass and other odds and ends. Everything was then tied together and covered with white ash paste. After the reassembled body was covered and filled in with the paste the person's skin was was refitted on the face and body. A mud mask was made, a wig was attached, and they were painted with manganese giving them a black color.
For a period of about 500 years, it was fashionable to make red mummies. These mummifiers didn't bother to disassemble the body, they just made slits in the body to remove all guts, organs and innards while allowing the body to dry out. They also cut off the head to remove the brains. The body was again packed with feathers and clay with sticks were inserted for strength. After they replaced the head they added long tassels of human hair and a clay hat to hold it all in place. They didn't usually bother to put the skin back on but did top off the mummy with a nice coat of red ochre.
Another way they were different from the Egyptians was that everyone that died in their culture got the mud treatment, not just the rich and famous.