Install

Install chruby and ruby-install using homebrew:

brew install chruby
brew install ruby-install
ruby-install ruby-2.6.2

Add the following to your ~/.bash_profile to use the ruby version we just installed:

source /usr/local/opt/chruby/share/chruby/chruby.sh
chruby 2.6.2

Update the bash environment and then install bundler:

source ~/.bash_profile
gem install bundler

Verify

Verify that Ruby has been installed properly

ruby --version
bundle -v