From charlesreid1

Installing Ruby on Mac Sierra:

Do it by installing RVM (Ruby version manager):

$ curl -L https://get.rvm.io | bash -s stable --ruby

This line should already be added to bash_profile:

[[ -s "$HOME/.rvm/scripts/rvm" ]] && source "$HOME/.rvm/scripts/rvm" # Load RVM into a shell session *as a function*