Commit an act of Mac mitosis when you have files and purposes in a single account that need to be divided into two.
One of macOS’s most beneficial features—and its biggest change from pre-OS X versions of macOS—is allowing multiple users to have unique accounts on the same computer. Sometimes, however, you might decide only after creating and using an account for a while that you might want it split into two or more macOS logins.
Perhaps you have an account in which you mixed personal and business purposes and decided that needed to be separated out. Or you had a single account for your family, and in the interests of privacy and home comity, you wanted to split those out.
Apple doesn’t have a “split account” option, as it’s perhaps a rare thing its users would want. But it’s not that difficult in the end. In my examples below, I consider turning one account into two, but you could also split one into three or more with the same principles.
Read more at MacWorld.com