Hello,
The best way is to edit the file SAPUILandscapeGlobal.xml located in %APPDATA%\SAP\Common. Please review note 2075073 - SAP Logon (Pad) 740: create/distribute server configuration file in the SAP UI landscape format, section "Creating the server configuration file(s) in SAP UI Landscape format after SAP GUI is installed for the first time".The uuid can be created randomly with an uuid generator (search on google). Once done, start your SAP Logon and you should see the systems you defined in the predefined entries.
Best regards,
Nicolas