Firstly the process starts with gutting the body. All inner organs were removed- except the heart. The heart had to remain in its place. It would testify for the lifeless person in the afterlife. Often an amulet (object that gives power) would be placed over the heart to protect it in its journey through the netherworld.
The brain was usually removed. A long, slightly hooked tool was put into the brain through the nose and swirled around to soften the brain. The head was then tipped forward and all insides of the skull were poured out through the nose. It is not rare