Migration Assistant is the easiest way to transplant the heart and soul of one Mac to another. While it used to be fragile and frequently failed or required multiple attempts, I’ve found it increasingly reliable in recent years. I’ve used it a few times in the last few months, and it worked with near perfection.
Migration Assistant has improved on the number of ways it lets you connect two Macs, and has become better at using the fastest method of connection. On newer Macs, the best way will always be Thunderbolt-to-Thunderbolt. This requires a Thunderbolt data cable. For somewhat worse but not terrible performance, you can instead use a USB 3.1 or 3.2 cable with USB Type-A or USB-C on both ends. (See this guide to determining what kind of USB-C-tipped cable you have if you’re not sure.)
If you have an ethernet port on both devices, you can connect a standard ethernet cable, but that will only deliver 1Gbps compared to the potential 10 to 40Gbps of USB 3.1 or Thunderbolt 3.
Read more at Macworld.com