First off, you must have the PLUS service level to access the File Uploads features.
Under a client's Case, you can upload documents under the following tabs...
Visit [Notes] tab
Click the [Add Note +] button (see screenshot here)
Visit [Documents] tab
Click the [Add Document +] button (see screenshot here)
Additionally, you can upload files to Bulletins and upload a client's photo by clicking the [Add Photo] button in the top-right corner of a Case (see screenshot here). There is a 5MB limit on all uploads. If you need this limit increased or need any help along the way please reach out the support team at 1-888-764-0633.