Download Postman:
mkdir temp cd temp wget https://dl.pstmn.io/download/latest/linux_64
Extract the downloaded archive:
tar xvzf linux_64
Apply root privileges:
sudo chown -R root:root Postman
Move it:
sudo mv Postman /opt/
Create a syslink, to be able to start Postman via the terminal:
sudo ln -s /opt/Postman/app/Postman /usr/local/bin/postman
Now you can fire it up by submitting
postman
into any terminal.