It’s easy to work on files together in macOS High Sierra. When you share a file in iCloud Drive, you and your team can all work in the same document — and never wonder who has the latest version.
Open the Finder, then choose iCloud Drive or a folder you’re syncing to iCloud (such as Desktop or Documents). Select a file (sorry, you can’t share a folder) and click the share button atop the window. Or just right-click a file and then click Share. You’ll see an Add People option in the share menu.
You can use Mail, Messages, Twitter, Facebook, AirDrop. When you select one of these options, a link to your file will be sent instead of an attachment.
There's also a Copy Link button on the Add People menu. It lets you copy the link to a file to your clipboard to paste when you wish.
(This how-to is based on my experiences and info on Apple's support pages — where the images sometimes come from.)