The branching model is well explained in his blog. If you’ve never heard about it, I really recommend you to read it.
About git-flow itself, there is a nicely done cheatsheet here
If you’re on a mac you can install it with brew
This also downloads the completion files. Which are in my opinion really useful when you start using a tool
However we can bring it to the next level by setting up some aliases. This takes very little time and saves you some keystrokes everyday. I couldn’t find any so I created my own: