Please follow this guide if you have not ever installed Ruby on your computer.
The TL;DR for Mac:
# global setup
brew install rbenv # ruby environemnt
rbenv install 2.5.3 # install ruby 2.5.3
brew install postgresql # database
brew install imagemagick # image-processing
# project setup
bin/setup
# run this to start the rails process
script/server
"THE (extended) BEER-WARE LICENSE" (Revision 42.0815): phoet contributed to this project.
As long as you retain this notice you can do whatever you want with this stuff. If we meet some day, and you think this stuff is worth it, you can buy me some beers in return.