Therefore, Time Machine will ask for your permission to reformat your external hard driveħ. A window will pop up asking if you want this disk to be your backup destinationĦ. Click on Select Disk and choose your external driveĥ. In the left side of the pop-up window toggle the switch from OFF to ONĤ. Go to System Preferences → Time Machineģ. One of the easiest ways to clean your Mac is to use an app such as MacKeeper that will easily and quickly delete all useless and duplicated files while keeping the useful stuff intact.Īfter cleaning your Mac, it’s time to back up your important files.Ģ. Therefore, you have to delete all this junk before backing up your data. Obviously, you don’t want to install a new macOS and have tons of junk files and unused apps. Why? Well, your Mac might get slow due to system junk and other unneeded files. Back up your dataīefore backing up your data it’s always a good idea to clean your Mac first.

Patience: Obviously, this process will take some time so you need to make sure you have an hour or two to spareĪfter making sure everything is ready, it’s time to prepare your Mac for the installation.

For this reason, you need an external HD that is at least the same size as your Mac’s internal memory

External hard drive (optional): You need to back up your data to save your important files before installing the new macOS.

Make sure the installer is fully downloaded (about 5 GB)

Good internet connection: You need to download the macOS High Sierra installer from the App Store.

Blank USB drive: You need a flash drive that has at least 16 GB of available storage space to create a bootable macOS High Sierra installer.Requirements to create a macOS High Sierra bootable USB driveĬreating a bootable drive with a High Sierra installer is quite simple. Installing macOS the clean way (using a non-startup drive).Creating a bootable USB using the Terminal.Requirements to create macOS High Sierra bootable USB drive.It’s not hard at all, and in this article, we will guide you through: It makes sense to create a bootable USB flash drive to install the High Sierra operating system if you want to quickly install it on several Macs without having to download the installer each time. The app will help you delete junk, duplicates, and unnecessary apps in a couple of clicks.

MacKeeper allows you to free up necessary gigabytes easily. Please note that before installing any system, you need to ensure there is sufficient space on your Mac.

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