1) Install Postman
Install the software "Postman" for your OS.
If you get
"error while loading shared libraries: libgconf-2.so.4: cannot open shared object file: No such file or directory"
You may first need to run this in the terminal:
sudo apt-get install -y libgconf-2-4
If you have an old computer you might find Postman being very slow or becoming unresponsive. In this case you can try the following alternatives: