By about 3,600 years ago, the Egyptians had advanced their expertise in mummification. Now, they had begun to eviscerate bodies while using various fluids to perfect the embalming process. In fact, we have quite detailed knowledge about the practice from the later Greco-Roman period – starting in the 4th century B.C. and lasting until the 4th century A.D. – because documentary evidence from that era exists.
Although we have that written evidence, though, it mostly deals with the ceremonial and religious practices rather than the practical mechanics of embalming and mummification. However, modern technology has enabled scientists to greatly increase their knowledge of the preservation techniques that were used by the ancient Egyptians on their dead.
Largely thanks to CT scanning of mummies, we now know about the basic steps used by the Egyptians in mummification. The first part of the process was to take out the internal organs, starting with the brain. A sharp object poked up through the nose broke up the brain, which would then liquefy and flow out.