A new OS X means a lot of new features and changes, which you can read about here. And the best thing for any Mac user to do before a major OS X update is to back up their files.

Did you know?

OS X Yosemite was last released years ago. It is no longer supported as well. However, it is still possible to run it. 

Furthermore, the steps outlined in this article may apply to any major OS update.

Why should I back up before upgrading to OS X Yosemite?

Shortly put, backing up your Mac is just a good practice, no matter the situation. In fact, when was the last time you even did a backup? Let’s pretend that your Mac crashes this very moment (knock on wood). Do you see how important having a backup is? Plus, you can never be sure what will happen when installing a new OS X on your Mac. Accidents happen — technology isn’t perfect.

What should I back up?

You should back up all of your important documents, files, and folders. Actually, just back up your entire drive! It’s a good idea to back up as much as you can so that you don’t have to worry about forgetting something. The Time Machine utility makes backing up files easier than ever. All you need are a few spare minutes and some sort of external drive (for example, a Time Capsule). So, let’s get to it!

Back up your Mac: the complete guide

How to back up your Mac

  1. Open Time Machine located in the Applications folder. If you’ve never used this app, after this first step, you’ll have to click on “Set Up Time Machine.”
  2. Next, on the right side of the Time Machine window, click on “Select Backup Disk.”
  3. Choose the drive you wish to back up your files to and click “Use Disk.”
  4. Now, click the “On” switch on the left-hand side of the main window of Time Machine.
  5. Over on the right, under the name of the storage device, there are three lines that say “Oldest backup,” “Latest backup,” and “Next backup.” Your new backup should start within the next 5 minutes.