First of all, it’s much faster to simply create a 1:1 copy of the entire drive rather than going through every folder looking for important files.
Our advice is to back up the entire hard drive – not just selected files. You probably have many important files stored on your Mac, and the last thing you want to happen is lose them.
Before You Restore Mac to Factory Settings A factory reset wipes out all data on your hard drive and restores all settings to their original state. If you want to sell your MacBook or restore it to its default condition, it’s a good idea to reset Mac to factory settings.