Lifewire.com has many excellent tutorials and Mac tips. This one is about how to quickly (relatively speaking) clone the Mac startup drive with the free, built-in Disk Utility on the Mac. Disk Utility actually performs the clone faster than Carbon Copy Cloner, and that is explained in the article.
https://www.lifewire.com/use-disk-utility-to-clone-macs-drive-4042367
John R Carter, Sr.