When you’re done with steps 1 and 2, you can proceed to the scary part - erasing and reformatting your Mac’s boot drive. We just published a step-by-step process for creating your bootable macOS High Sierra installer using this free application, so take time to read the process and to make your installer disk However, there’s an easy way to do this step, and that’s to use DiskMaker X 7. You can create a bootable macOS High Sierra install disk by knowing just what Terminal commands to use. Step 2: Create a Bootable macOS High Sierra Installer Remember, your Mac will be completely erased and if you have not copied your information to another location, you will lose it.

Now, what kind of backup to you want to do? A Time Machine backup of your entire system is quite acceptable, or you can use an app like Carbon Copy Cloner or SuperDuper! to create a bootable clone of your Mac.įor those really important files, such as important documents, photos, videos, and so on, you may want to make a separate backup onto other media or to a cloud service like iCloud Drive or Dropbox.ĭo NOT go further without making a backup. It’s very useful to also have copies of all of your license information for Mac apps, since those that require a license or activation will need to be set up after your clean install. In addition, be sure that you know all of your online account passwords and logins - for this, a password manager like 1Password can be very useful.

Make sure that you have access to all installation media for your apps (developer websites, Mac App Store, DVD or CD), and it’s a good idea to make a Note of all apps that you wish to re-install. Clean installs are also useful if a software or system software update has somehow trashed your existing operating system or if you have replaced a hard drive.īe sure you have plenty of time available to complete the complete install, as it can sometimes take as much as a day to go through all the steps.Īs noted, we’re going to completely erase everything on the Mac. In many cases, a clean install can improve the performance of a sluggish Mac. The idea behind a clean install is to start with a completely bare machine, getting rid of any old data, files, preferences, settings, old drivers, apps you no longer use, and so on. In this post, we’ll describe how to do a clean install of macOS 10.13 High Sierra.īefore we get started, make a decision as to whether you want to do a regular update or a clean install, because a regular update is much easier to perform than a clean install.

What’s a clean install? That means that the hard drive is erased completely and reformatted, which removes not only the current Mac operating system but all data, files, applications, you name it… Just think of it as a brand new computer having the operating system installed on it for the first time. Sometimes it’s a good idea to do a clean install of a new Mac operating system version.

How to install high sierra