To upload and download documents directly to and from your clients:
1. Navigate to Clients, then select Client List
2. Select the client you're looking to upload files to
3. When their individual profile is displayed, select the documents tab
4. From there, you would click on either Upload File or Create Folder (if you wanted to organize files into folders)
5. One thing you don't want to forget is to make sure you click on "Share" next to the files and folders that you want your clients to see in their portals.