After some advice on here seriously thinking of getting a portable SSD drive Can I transfer all my data and software from my internal to the new SSD drive and then use it as my main drive. Where would I find instructions on how to do the transfer.
Hook up SSD in a USB3 or TB container, connect to appropriate port, format OS Extended Journaled or APFS depending on the Mac model and operation system, copy, then with the SSD still attached go into System Preferences > Startup Disk and select the SSD which will appear there if you have made it bootable.and use cloning software such as SuperDuper or CarbonCopyCloner.
As Harry stated, once all your data is transferred and the SSD is made bootable, you can then use it to boot your Mac just as if it were your internal drive.
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