When running Luminair for the first time, the app will ask whether you want to enabled iCloud. Projects, fixtures, images and other related files will be synced to iCloud and to other devices linked to this same iCloud account and running Luminair. (please be aware of licensing issues for multiple users)

If you originally set up Luminair without enabling iCloud, you can turn it on in Luminair's Main menu > Settings > iCloud.

Please note that iCloud is used for personal syncing and it's not possible to sync between iCloud accounts. If Apple ever enables that capability we would likely add support for it.