The idea behind a macOS Clean Install When you install a new major version of OS X, or after some time has passed, it is a good idea to do a clean install (that is, to erase the disk you are installing OS X onto as part of the installation process). That will make your Mac run blazingly fast for a few months or more, and many people report that it fixes longstanding problems they’ve had too.
It used to be common practice to occasionally run a clean install, and then manually migrate all the files and settings over in order to get a completely fresh start. However, it has been shown in recent times that in the vast majority of cases if you simply run a clean install, then duplicate your old home folder to your new disk, you will get all of the same advantages as a clean install followed by manual migration, with a small fraction of the effort. Mac Clean Install Procedure Here is the clean install procedure which can be performed at least every time a new version of macOS is released:. Download the macOS installer from the App Store. You can download macOS High Sierra by clicking. Backup all the data to an external disk with a clone.
I'm going to walk through the steps of making a bootable USB flash drive on Mac OS X.
Two options are to use (a free utility which can copy and paste an entire bootable volume), or (a paid, fully featured backup utility with unique incremental backups capability) for that. Create a bootable USB Installer with and boot from it. Erase the startup disk and install macOS onto it. Boot up from this newly created startup disk.
Note: The Finder’s built-in “Copy” and “Paste” will not work for the following. Go to the backup disk and use (free) or to right-click and select Copy on the home folder (eg: External Backup/Users/Bob) and then Paste on the Macintosh HD/Users folder on the startup disk. This migrates all of your personal data and settings to your new home folder. Then migrate the applications by selecting Copy on the External Backup/Applications folder on the backup disk then Paste on the startup disk (eg: Macintosh HD). This will copy all of the applications which are present on the backup disk but not present on the startup disk to your new Applications folder, and automatically skip any applications which are already on the startup disk. At this point, after a reboot and some minor adjustments (the Dock may not have your previous configuration for example, if you did this while logged into the same user account as you just updated), your new OS should be indistinguishable from your previous one, while being faster and smaller due to reduced clutter.
How to make a bootable USB stick for macOS installation Macs made in 2010 and later do support Internet Recovery. This is very handy if you have to install your operation system again. If you have an older Mac though or a slow internet connetion, a bootable USB stick or SD-card may be a clever idea. All younger Macs can enter Internet Recovery by pressing option +command + R during startup. A globe will appear and the machine will download all necessary software over the internet. This is quite cool, but has has a few disadvantages: It takes some time, the version of operating system installed is always the one the Mac originally came with, and you have to have an internet connection.
You can bypass all that with a boot medium that you can make on a second machine. How to: Make bootable installation medium for OS X and macOS Only three things to prepare You need a medium.
Obvious, sure. ? Your USB stick or SD-card must have a minimum of 8 GB.
The next step is downloading the OS X or macOS version you’d like to install later. Lets assume that is macOS Sierra. To prepare a bootable medium with this operation system, you need the install package of it. If you just updated your Mac to this version, you may find it in Applications.
If there is an Install OS X Yosemite.app that has the size of a few gigabytes, you are already done! Otherwise, open the App Store and download it again. The third ingredient is the great tool DiscMaker X that you can. DiskMaker X does the work for you and creates a bootable medium So now we have everything we need, we can start creating a bootable medium: insert the USB stick or SD-card into the Mac and open DiscMaker X. Choose the system you like (and downloaded before) in this case macOS Sierra.
DiscMaker X now should find the installation package by itself. After that, choose the USB stick or SD-card that you would like make bootable. Beware, that all data on this medium will be deleted! DiskMaker X will now take its time and finish eventually.
A bootable medium for installation of macOS and OS X You did it! Now you have a bootable medium, that can install macOS Sierra on supported Macs, without waiting for downloads or the need to install an older version first. Preparation is everything! ? Use of a bootable medium Just press the option key during startup. Choose boot medium option key Lists all discs the Mac can boot from Your Mac will now list all drives that it can boot from.
We choose our installation medium of course and start by formatting the drive and then install our operation system.