Install brew from http://brew.sh/index.html
This will install xcode command line tools, which can take some time (~20 minutes).
brew install git
You may want to setup a development environment like I do with vim.
Follow the instruction here
# Ensure the version installed is the version set in .ruby-version
rbenv install 2.5.1
gem install bundler
brew install postgres
psql template1 -c '\du'
# create a user called 'root' with no password
createuser -a -d -U USER_DISPLAYED_ON_PREVIOUS_COMMAND -P root
brew install redis
bundle install
Create .env
from .env.example
bin/setup