Wiki for the AzerothCore Project available here: http://azerothcore.github.io/wiki
First of all install the ruby development environment using this guide.
After that install bundler using gem and run bundler install:
$ gem install bundler
$ bundle install
Well, now you can run locally the app using:
bundle exec jekyll serve
If everything succeds, you can visit your web app at http://127.0.0.1:4000/.
Any problems? Open a issue.