Here is how to create sync pair which will sync two cloud accounts:

1. Click the “Sync & Integrate” tab:
   
2. If you are not redirected to the wizard, click “Add New Sync Pair” in the Sync & Integrate tab:
   
3. Choose “Sync two cloud accounts”:
   
4. If you choose to sync two cloud services, you will be forwarded to the sync wizard:
   
5. Follow the instructions to sync folders between your cloud services:
   1. Click on first cloud service
   2. Authorize it
   3. Select folder to sync
   4. Select on second cloud service
   5. Authorize it
   6. Select folder to sync
   7. Select options such one one-way or two sync sync, replicate deletion, etc.

BTW, you can also search for the instructions on the kind of sync you want to create:
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