A feature that Apple added in macOS Sierra is called Optimize Storage. It lets you free up storage space by having the system automatically keep things in iCloud. Here’s how to turn it on and optimize Mac storage.
Optimize Mac Storage
When you optimize Mac storage, macOS will automatically store content in the cloud whenever extra storage space is needed. This includes files, photos, movies, email attachments, and other content. To start:
- Click the Apple () icon in the menu bar, and select About This Mac.
- Click on the Storage tab.
- Click on Manage…
- You’ll see recommendations for optimizing storage across several categories.
You can click Store in iCloud, optimize iTunes content, have your Trash automatically empty every 30 days, and reduce clutter by deleting big files you don’t need anymore. When you choose the Store in iCloud category, you’ll see options for Desktop and Documents, and Photos.
Desktop and Documents means that all files in those two locations will be stored in iCloud. When storage space is needed, only the files you recently opened will be kept on your Mac. Files that are in iCloud will have a download icon next to them. You can double-click these to download the original file.