How to send popup message to a specific user in SAP?

How to send popup message to a specific user in SAP?

Enter the  Tcode SE37  in the command filed ,  Function builder: initial screen will open

Enter the function module  TH_POPUP,  then press the execute button,

the module function screen will open

In this screen you have  to  fill the client number,  client name(You want to send the text message ),  &  message, then press the  execute button