How can I install Ruby on Rails 3 on OSX?

Question

I got a White Macbook and I have to go to a conference in 10 hours but I\'m having a lot of problems.

First, I wanted to have Rails 3, so I used MacPorts to install

Answer 1

To easily setup Rails 3 on osx machine the only thing you need to do is follow this brilliant (as always) Railscast, here for the transcription

You can also see comments to check for problems and eventually solutions.