You can partition your Mac and boot another operating system alongside your current one.
If you've always wanted to partition your Mac's hard drive so you can run a separate operating system in tandem with your current one, it's surprisingly easy to do so thanks to Apple's built-in disk utility program. Here's how to partition your Mac.
What is a disk partition?
Partitioning your Mac is basically splitting your hard drive into separate, usable systems. It makes it possible to run two separate operating systems on one device, like Windows and OS X, or El Capitan and macOS Sierra.
It is important to note that partitioning your hard drive also splits up your available hard drive space. Each partition will take up a portion of your usable storage. So, if you are running low on storage capacity on your hard drive, we don't recommend partitioning; try using an external drive, instead.
Before you start
The most important thing to do before making any changes to your hard drive is to back it up. Seriously. Back it up. Please. Time Machine is the easiest way to back up your data if you don't already have another system in place.
Make sure you have enough free disk space to properly run a secondary operating system. Shoot for at least 30GB free.
How to create a partition on your Mac
- Open Finder from your dock.
- Scroll down and open the Utilities folder.
Double-click to open Disk Utility.
- Select your hard drive in the Disk Utility window. It will be the first drive on the list. It might be named "Fusion," or "Macintosh HD."
- Click on the Partition tab.
Click the plus (+) button.
- Change the size of the partition you wish to use by dragging the resize controls. The used space is represented in blue.
- Name the new partition.
Disk Utility will check the disk and make changes. This will take several minutes.
How to install macOS Sierra on your partitioned hard drive
Once your drive is partitioned, download macOS Sierra on your main partition first. Then, choose the partition when you get to the installation step.
- Download macOS Sierra on your main partition.
- Select Continue when the download is finished and ready to install.
- Agree to the terms.
Click Agree to confirm that you have read the terms.
- Select Show All Disks to switch from your main partition.
- Select the partition you wish to install the software on.
The installation helper will allow you to transfer information from your current operating system, or you could choose to do a clean installation to start your Mac from scratch.
How to switch partitions
Your Mac will automatically restart using the beta partition. If you want to get back to your OS X install, however, you'll have to use the Startup Disk app to switch partitions.
- Click the Apple icon () in the upper-left corner of your screen.
Select System Preferences... from the dropdown menu.
- Select Startup Disk.
Click the Lock in the lower left corner of the window to unlock and make changes.
- Enter your system admin password.
- Click OK.
- Select your main hard drive.
You can also restart your Mac and press the Option Key when you hear the startup chime. This will take you to the Startup Manager and you can select your drive from there.
Do you have any questions about installing a partition or downloading macOS Sierra onto a partitioned drive? Let us know in the comments.