Download postman and extract it in your home folder.
Create a postman.desktop file in local share folder and paste the following script in your local share file :
nano ~/.local/share/applications/postman.desktop
[Desktop Entry]
Version=1.0
Type=Application
Name=Postman
Icon=/home/{user_name}/Postman/app/icons/icon_128x128.png
Exec=/home/{user_name}/Postman/Postman
Comment=Supercharge your API workflow
OnlyShowIn=Unity;GNOME;
StartupNotify=false
StartupWMClass=Postman
X-UnityGenerated=true
Categories=Development;IDE;
Here replace your username with your