Apple + How To

How to Prepare Your Mac for macOS Sierra

Posted on by

How to Prepare Your Mac for macOS Sierra

For the latest version of this article, see How to Prepare Your Mac to Upgrade to macOS Big Sur.

How to Prepare Your Mac to Upgrade to macOS Big Sur: the Ultimate Guide

As you’ve probably noticed by now, the next version of Apple’s desktop operating system, macOS Sierra, is due to be released in the fall. Following the annual schedule that Apple has kept to for some time, operating systems for both the Mac and for iOS will make their debuts in the coming weeks. And, as has been the case for several years, both of these upgrades will be free.

What does this mean for you? You most likely want to update your Mac, but there are a number of things you should consider doing before updating. And for some of them, it’s useful to plan ahead. In this article, I’m going to explain how you can prepare your Mac for macOS Sierra. Following are some answers to the most frequently asked questions about upgrading to macOS Sierra.

Is my Mac compatible with macOS Sierra?

The first thing to find out is if your Mac can run macOS Sierra. Apple hasn’t published this information on its website yet, but during the presentation of the new operating system at the WorldWide Developer Conference in June, a slide revealed the following compatibility information:

Late 2009 & later
– MacBook
– iMac

2010 & later
– MacBook Air
– MacBook Pro
– Mac mini
– Mac Pro

This is simple, for the most part, with the exception of exactly what “Late 2009” means. Apple often names its products like that, using “Early” and “Late” to identify models.

It’s easy to find out your Mac’s pedigree. Just click the  Apple menu and choose About this Mac. You’ll see a window with information about your computer. For example, I’m writing this article an a “MacBook (Retina, 12-inch, Early 2015).”


So if your Mac matches one of the above dates, then you’re good to go.

If your Mac is too old, you could always buy a new Mac, or even a more recent used model. New Macs will start shipping with macOS Sierra shortly after its release, and even if you buy a Mac that doesn’t have macOS Sierra, you’ll be able to easily update to the new operating system.

How much space will I need to upgrade?

Apple hasn’t published that information yet, but if the specifications for OS X El Capitan are a guide, you’ll need around 9–10 GB free to upgrade. If your getting tight on hard disk (or SSD) space, read this article about how to delete files that take up space on your Mac, and this article about how to reclaim space on your drive using Intego’s Mac Washing Machine.


Regardless, if you only have enough free space to install macOS Sierra, then you should seriously consider cleaning up your hard drive. Operating systems don’t run well if they don’t have free space for temporary files, and for virtual memory files, which can be several GB.

Will my Mac keep up with the new operating system?

It’s hard to tell. If your Mac is on the low end of the compatibility list—those models from late 2009 or 2010—you may find that things get a bit sluggish. This is because your Mac may have a slow processor that isn’t up to the demands of the new operating system, or because you don’t have enough RAM.

While you can’t update the processor on your Mac, you may be able to add more RAM. This is possible on most iMacs, the Mac Pro, and some Mac mini models. For laptops, it’s a bit more difficult; check around to see if any company offers upgrades for your laptop. This will involve a technician opening up the Mac and performing surgery; not something I’d recommend doing at home. If you want to try, though, check the iFixit website; they have great teardowns and walkthroughs that may help.

As to how much RAM you’ll need, the specs for El Capitan call for a minimum of 2 GB, but I recommend having at least 4 GB, or more if possible. My MacBook has 8 GB, and that seems to me the minimum to be comfortable running multiple apps, but if your use is more limited, 4 GB should be fine.

Another upgrade you can make, which would have a notable effect, is swapping your hard drive (if your Mac has one) for an SSD. Hard drives—especially in portables—are relatively slow, and switching to an SSD will make your Mac feel like it’s stopped by for a drink at the fountain of youth. The downside is that SSDs are more expensive, and you’ll need to settle for one with less storage. For example, my iMac and MacBook both have 256 GB SSDs, but I use an external drive connected to my iMac to hold my media files. Having the operating system on an SSD is important; the media files, which aren’t read often, don’t need to be on a disk as fast.

Should I back up my Mac before upgrading?

You probably already know the answer. I’ve always been a belt-and-suspenders guy as far as backups are concerned, and I recommend using at least two types of backup. You can use both Time Machine, which is part of OS X, and Intego Personal Backup. They back up your files in slightly different ways, and it never hurts to have more than one backup in case one of them becomes corrupted.

While macOS Sierra isn’t ready to launch at the time of this writing, if you don’t have a backup of both your startup disk and any external drives you use, you should certainly get into the habit now. And, when you’re preparing to upgrade to macOS Sierra, you should clone your Mac’s drive right beforehand, in case something goes wrong.

Should I check my drive before upgrading?

Yes, that’s a good idea. Open Disk Utility, which is in the Utilities folder of your Mac’s Applications folder. Select your drive and click First Aid. The app will run a check on the drive, its catalog information, and your files. If there are any repairs to be made, it will be able to carry out most of them.


If you do have more serious errors, then you’ll need a specialized disk repair app. I’m a big fan of DiskWarrior; you can read my review of the latest version from early 2015. (NOTE: As of DiskWarrior 5.2, it does not support APFS formatted drives. APFS was introduced in macOS High Sierra, a year after this article was published.)

Should I migrate my data or do a clean installation?

In most cases, simply running the macOS Sierra installer will be sufficient. This installs the new operating system over your existing files, and doesn’t touch any files that aren’t part of the operating system.

That said, there are good reasons to do a clean installation (I’ve written about them in this article). If you do want to do a clean installation for macOS Sierra, you’ll need to clone your startup drive to an external disk, and boot your Mac from the clone, erase the drive, then run the installer.

If you do this, make sure to have two backups of your startup volume. Since you’ll be erasing the drive in your Mac, if something goes wrong with the clone, then you’ll be in a lot of trouble.

I use [App Name] and I simply can’t work without it. Is it safe to upgrade?

This can be a problem. If you have an app you simply must use, check with the developer to make sure it’s compatible with macOS Sierra. Developers have had access to beta versions of the new operating system since June, but there are often cases of apps that aren’t ready on release date. Check any essential apps before upgrading.

You may also have helper apps or drivers—such as for storage devices, printers, scanners, and others that you relay on—that might not be updated. Run an inventory of your most important apps, and don’t forget hardware that needs its own software. If everything is compatible, make sure to upgrade all that software first, then move on to macOS Sierra.

macOS Sierra will be an excellent upgrade, but you should make sure to prepare your Mac so you don’t have any surprises. And if something does go wrong, you’ll have backups to be able to recover all your files. Just plan ahead.

Did we cover all your concerns about upgrading to macOS Sierra? Have other questions about preparing your Mac for macOS Sierra? Leave a comment below!

About Kirk McElhearn

Kirk McElhearn writes about Apple products and more on his blog Kirkville. He is co-host of the Intego Mac Podcast, as well as several other podcasts, and is a regular contributor to The Mac Security Blog, TidBITS, and several other websites and publications. Kirk has written more than two dozen books, including Take Control books about Apple's media apps, Scrivener, and LaunchBar. Follow him on Twitter at @mcelhearn. View all posts by Kirk McElhearn →