Any Report that you have access to through the Manage Clients Dashboard can be copied to a new report. You can then edit the copy and save it as a new report with the changes applied. This can be useful if you have multiple similar reports you need to create. Or, if you have access to a shared report (which are read-only) but need to make changes, you can make a copy and edit the copy for your own use.
The copy of the report becomes the current report you are viewing. You can now edit the report to your needs and save whatever changes you make.