Fast storage remains expensive; slower storage not so much. That can lead you to opt for relatively little SSD storage when upgrading to a new Mac, especially compared to hard disk drives you might have installed or accessible with your previous Mac.
An external hard drive is the best and easiest strategy. I have a 1TB Fusion Drive on my iMac and both 4TB and 8TB external drives for cloning the startup volume and for holding media and archives.
However, you might prefer to not have to maintain external storage and deal with maintaining local or internet-hosted backups. If you’re a laptop user, external storage is often a hassle. Instead, you might want to lean on the cloud. The easiest and most affordable cloud storage methods follow.
Sync and store offline
Virtualize your storage by seeing all your files and folder in the Finder, but letting them stay entirely offline and in the cloud except as you need them. Both iCloud Drive and Dropbox are the most notable and affordable in this category, and both offer great integration into macOS. If a file isn’t stored on your Mac, you can simply double-click or otherwise try to access its representation in your filesystem, and it’s downloaded from the cloud. This approach does require a healthy broadband connection.
Read more at MacWorld.com