Postman can be downloaded from here.
Select the Method(SET/GET..) → Enter the URL / Service / API → Navigate to Params Tab and enter if there is any
Navigate to Authorization Tab → Enter relevant Type → For current case it is Basic Auth → Enter SAP Username & Password
Navigate to Body Tab → Enter Payload → Beautify (Optional)
Select Radiobutton raw → Select JSON from Dropdown
Click on Send → Response will be populated in bottom part
How to clear cookies:
SAPCODES 
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