How to I update my Mac? How do I install Mac OS X El Capitan, and how to I install macOS Sierra when that comes out?

Apple didn't mention Mac, MacBook or macOS Sierra at its iPhone 7 launch event on 7 September. In fact, Apple announced the release date for its upcoming OS via its own website, and is to be released to the general public today, 20 September 2016. Based on previous iOS and macOS releases, we expect macOS Sierra to become available to download at roughly 6pm (BST) with users able to download the software from the Mac App Store. Read on for the latest, as well as how to download macOS Sierra once it's out later today. 

macOS Sierra, Apple's next update to its OS X desktop operating system software, has bees available as a Public Beta and Developer Preview since June 2016, prior to its autumn 2016 release. In this article we explain how to download and install macOS Sierra on your Mac, or Mac OS X El Capitan on your Mac if you want the current version of the operating system. We'll walk you through the install and update process, and guide you past the potential headaches and problems you may encounter.

Updated, 20 September to include the news that macOS Sierra is due to launch today

Read more: macOS Sierra new features & release date | macOS Sierra vs Mac OS X El Capitan | How to downgrade from Sierra back to El Capitan

How to prepare your Mac for macOS Sierra

macOS Sierra is pretty easy to install. However, before you perform any big update to your Mac, you should complete a few tasks to ensure that your Mac is ready to go.

Back up your Mac before installing

Backup your Mac before installing OS X

No matter what, we recommend a full back up before you install macOS Sierra. Apple makes it easy to back up your Mac using Time Machine, so there is no excuse not to create a Time Machine backup before installing macOS Sierra.

Follow these steps to back up your Mac using Time Machine.

  1. Connect an external hard drive to your Mac. Choose a new hard drive, or one that you don't mind erasing.
  2. An alert may appear asking if you want to use the drive to backup your Mac. If so,  Use as Backup Disk.
  3. If not open System Preferences > Tim Machine and click Select Backup Disk. Choose the external drive.
  4. Switch Time Machine to On.
  5. A progress bar will appear in the Time Machine system preference pane. Wait for the Time Machine backp to complete before continuing with the macOS Sierra installation.

Read next: How to back up your Mac | What to do if your Mac doesn't finish installing an update

How to install macOS Sierra

Follow these instructions to install the macOS Sierra update on your Mac. 

  • Once you've backed up your Mac, launch the App Store and search for macOS Sierra.
  • Click Download to initiate the download, and fill out your Apple ID information if prompted. Download progress will appear in your Purchases tab.

Once the download has finished, you'll see a macOS Sierra installer launch. Follow the on-screen insturctions to finish installing the software update, which should take around half an hour depending on the spec of your Mac.

How to install macOS Sierra on an external hard drive

Luckily you don't have to install the update on your Mac at all - you can install it on an external hard drive. 

You'll want to use a fast drive if you can - Thunderbolt drives are comparable to the internal drives on a Mac, but if you do not have a Mac with Thunderbolt then consider using a USB 3.0 drive.

Adding a second hard drive, formatting it and installing macOS Sierra on it is the safest way to get a good look at the new operating system. It'll leave your current configuration intact and allow you to play around with Sierra.

To install Sierra on a external hard drive follow the following guide:

  • Connect the external hard drive.
  • Launch Disk Utility (choose Go > Utilities to find it).
  • Select the drive in the sidebar (the root drive, not the volume it contains).
  • Click Partition.
  • Ensure that Partition Layout says 1 Partition.
  • Give it a name like "macOS Sierra".
  • Click Options and ensure that Guide Partition Table is selected. Click OK.
  • Click Apply and Partition.

Now download the macOS Sierra installation from the Mac App Store and follow these instructions to install the beta on the hard drive:

  • Download the macOS Sierra installer from the App Store, and open it once downloaded.
  • Click Continue.
  • Click Agree and Agree.
  • Click Show All Disks.
  • Highlight the external hard drive.
  • Click Install.
  • Enter your Admin password
  • To run Sierra, open System Preferences > Startup Disk. Select the drive you wish to start up the Mac and click Restart. You can also hold down Option during startup to pick the drive you wish to use to start up the Mac.

How to dual boot OS X El Capitan and macOS Sierra on a Mac

If you don't have a spare external hard drive (or the one you have is slower than you would like) you can partition the main hard drive into two separate drives and then install macOS Sierra on one and OS X 10.11 El Capitan on the other.

The only issue with partitioning your drive is that you will have to wipe your internal hard drive and reinstall OS X 10.11 El Capitan along with the new software.

If you want to keep any of your current work, you need to create a backup of Mac OS X 10.11 El Capitan and ensure that it will fit on your smaller partitioned drive.

To create your partition follow these instructions:

  • Boot Mac OS X into recovery mode (Hold down Option during startup).
  • Use Disk Utility in recovery mode to wipe the main hard drive and split it into two partitions.
  • Use the Install option in Recovery to install OS X 10.11 El Capitan onto the main partition.
  • Next restore the data to El Capitan from your Time Machine (or other backup).
  • Follow the steps above to install the macOS Sierra Preview onto the second partition.

How to get macOS Sierra features on El Capitan or earlier

Let's suppose you don't want to install a beta OS on your Mac - which makes a certain amount of sense, given that beta software is by definition unfinished and may cause bugs, glitches or worse. Or perhaps you've got an older Mac that can't run Sierra at all. Is there any way for you to get access to the new features?

Yes there is.


Apple's spoken assistant comes to Mac in the Sierra upgrade and you can speak the usual commands you might be used to on your iPhone, iPad and Apple TV - from asking what the weather is like, to where a file is located, to asking Siri to create a new calendar event.

Although it's not a straight swap-in, Flashlight radically expands the existing Spotlight feature of OS X Yosemite and El Capitan - you can summon Spotlight in the usual way and type Siri-like instructions like "call Frank" or "weather today". Best of all, Flashlight is free, and there are loads of plugins that expand it in nearly every imaginable direction.

If you fancy a more powerful solution, try Alfred. This works alongside Spotlight, rather than extending it, but you can input all kinds of commands - from telling your Mac to empty the trash, to searching the web. You can create your own workflows and automations too, so the only limit is your imagination.

Get macOS Sierra features now: Siri


Apple's image cataloguing and sharing app gets a number of new features in Sierra, and perhaps the most useful is Intelligent Search. If you want to find photos of a beach, for example, then you can type "beach" as a search term. Photos uses “advanced computer vision technology” to identify the actual content of your photos.

This might sound like science fiction but Google Photos pipped Apple to the post earlier this year with its own version, utilising neural networks and machine learning. Type "woman in red in Grimsby" and Google Photos should find photos matching the query.

Google Photos also does a pretty neat imitation of the Moments feature that's coming in Photos on Sierra, which aims to automatically create photo collections based on people, places, holidays and more.

And the best news? Google Photos is not only here right now for OS X and iOS, but is free for the basic package that allows unlimited uploads - and because it stores your images in the cloud, it can save you hard disk space. It comes with a small Mac app that'll automatically upload photos too. Check out our review of the service that's part of our round-up of inexpensive image editing and cataloguing apps.

Get macOS Sierra features now: Photos

Auto unlock

If you've got an Apple Watch and a Mac running Sierra then you'll rarely need to type your login password because the two work together to automatically wake a sleeping Mac and log you in before you've even planted your bum on the chair.

However, several third-party apps already implement something very similar. For example, Near Lock (£2.99) has offered been available for a few years, although in this case the ability to unlock your Mac is extended not just to your Apple Watch but also to your iPhone.

Knock (£3.99) and MacID (£2.99) have also been offering something almost identical for a year or two. Both let you use TouchID on your iPhone to unlock your Mac and, if you've an Apple Watch, extend unlocking to a tap on your Watch screen.

Get macOS Sierra features now: Auto unlock

Universal Clipboard

If you've got an iPhone running iOS 10, and a Mac running Sierra, the clipboard will essentially be shared between the two. Copy text on an iPhone and you can instantly paste it on your Mac. Copy a photo on your Mac and you can paste it on your iPhone.

Although it's not quite as seamless, ClipAgent (£4.49) lets you do the exact same on older versions of OS X/iOS. Alas, you have to open the ClipAgent app each time to opt to transfer the clipboard data to/from the iPhone or Mac, but this is perhaps a better approach in any event because it avoids the risk of unknowingly overwriting important clipboard data on each device.

Also worth investigating is Heapo (free), which is more of a clipboard manager app for iOS although it features Drobox cloud syncing for the clipboard contents and a Chrome browser extension. A client for OS X is going through beta testing and will be here soon.

Get macOS Sierra features now: Universal Clipboard

iCloud Drive

In addition to the contents of the special iCloud Drive folder, when Sierra hits you'll be able to sync your desktop and Documents folder using iCloud. This makes working across two or more Macs much easier.

Technically speaking, however, there's no reason why you can't sync the desktop and Documents folder using ANY cloud storage service – and you can do so right now. For example, Dropbox provides instructions on how to do this, and there are several guides online. Apps like MacDropAny (free) make it a cinch to sync any folder on your hard disk with virtually any cloud service - including iCloud Drive.

Get macOS Sierra features now: iCloud Drive

Apple Pay integration

Alas, we end on a sour note. In the Safari 10 web browser supplied with macOS Sierra you'll be able to make purchases using Apple Pay, provided your Apple Watch or iPhone is nearby (you'll need to use this to confirm the purchase). Perhaps surprisingly from a commercial viewpoint, there appears to be no plan to bring Apple Pay to earlier releases of OS X - the release notes for betas of Safari 10 for Yosemite and El Capitan make a point of saying it's not included.

The Safari Technology Preview exists to test upcoming technologies on OS X, and currently implements Apple Pay - although there's nowhere to use it right now because sites implementing Apple Pay are still waiting for Sierra before going live. However, whether Safari Technology Preview will allow users of older releases of OS X to utilise Apple Pay on websites remains to be seen. We reckon it's possible, but unlikely.

Read page 2 to find out how to install El Capitan if you have yet to update to Apple's current version of the Mac operating system.