You're looking at the source code of my brand-spanking new blog. Feel free to fork and mess around with it.
Make sure you've got a clone of the source code. After that, we need a few ruby dependencies:
sudo gem install jekyll sudo gem install github-pages
On Ubuntu, you might need to run the following first:
sudo apt install zlib1g-dev ruby ruby-dev
Then, from the root of the blog just run:
jekyll serve --watch
This will typically start a server on port 4000.