Getting up and running on a clean local checkout

tl;dr: Perform the below, or fallback to GitHub's instructions.

• Install rbenv (e.g. using brew)
• Install some local version of Ruby through rbenv so that Bundler can install the Gemfile dependencies without resorting to sudo - rbenv install -l followed by rbenv install $VERSION (for whatever version you want to install)
• Make sure that the new version is used - rbenv local $VERSION or rbenv global $VERSION
• Install the dependencies (bundle install)
• Serve the site (bundle exec jekyll serve)