Through this method, you can easily delete your files that are important and personal so that the person getting the mac can’t access them. How to Wipe Your Mac and Reinstall macOS from ScratchĪnd if you are selling or giving away your mac to either a random guy that you found on eBay or craigslist or your relative. 1.2 Step 2- Securely Wipe your Hard Drive (Optional):Īre you bored using your old mac and its operating system? Or you are just looking for an efficient way to clean and keep your machine updated? For the first scenario, we are going to show you how you can uninstall and then reinstall your macOS and for the second scenario, yes this method that we are going to show of deleting your files and reinstalling a fresh version of macOS can help you get a new perspective for your machine.1.1 Step 1- Boot from Recovery Mode or an Installer:.1 How to Wipe Your Mac and Reinstall macOS from Scratch.