To add a new client to your Medusa software, you will likely want to add them as a new Profile.
To create a new profile go to Configure→Profiles or click the shortcut icon: 
You will then see the following screen:
Go ahead and check the box to enable profiles if it is not already and then click Add New Profile and then you will see the following two screens (enter a new client name in the first and click OK), then select an existing profile to duplicate:
You will now see your new client profile listed and it will be selected in the dropdown box at the bottom as the currently selected profile to edit in any of the configuration settings. If this is the first time this has been done, the original profile will be labeled here as Original Profile (replace this label), so go ahead and change that to an appropriate name for this client or profile.
At this point you should go back through all your configuration settings and change any specific setting that will be different for this new client. Examples of things that likely will change are the Client ID (in ID Fields), possibly some Timekeepers, and the LEDES file name or the folder the files are saved in (in Invoice Description & Misc. Settings) for a given client if you have customized this or would like to.
When you finished making changes, click Finish and you should see your new profile as a new button on the main screen. Restart Medusa in order for the button to be active. Then, to run a profile with its unique settings, just click the appropriate button:
