Yay! Come help. Check out the issues. The easiest way to serve the website locally is to follow the development guidlines below. Let me know if there are any hitches there!
It's really helpful to have an idea of what the site is trying to achieve so before you dive in it would be great if you can have a look around codeofconduct.io.
Also I try to use the branching model described here. Don't worry about it too much but the main thing is to make pull requests against the develop branch. Not master!