
How do I use Disk Utility to reformat my hard drive? Otherwise, you can skip this step and do it from the Utilities page during the macOS or OS X installation. If your Mac doesn’t work, you can do this using a second Mac and an external hard drive caddy. It’s easy to reformat your hard drive using Disk Utility in macOS or OS X. Disk Utility can be used to format external drives as well. If you don’t want to lose data from your hard drive, export the data or back it up before continuing.

You may need to reformat your new hard drive before installing macOS or OS X on it.

Download the relevant macOS or OS X installer from Apple, then use Terminal to create a USB installer you can boot up from.Install macOS or OS X from Internet Recovery Mode, which you can boot into by holding option+command+R while your Mac powers up.If you’re tech-savvy but don’t know where to start, use these Quick Tips to point you in the right direction for getting macOS or OS X on your drive:

Simply follow the instructions below to install the latest compatible version of macOS or OS X on your new hard drive. So, it doesn’t matter if you want a clean slate on a second-hand MacBook or if you replaced the drive in your age-old machine, we’ve got you covered. In this article, we’ve given detailed instructions for each method. Fortunately, there are also several ways to do it, ranging from Internet recovery to installation discs.

There are several reasons you might need to install a new copy of macOS or OS X on the hard drive in your Mac or MacBook.
