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
First you need to install RVM, then the latest version of Ruby. Next you'll set that version of Ruby as the default. Finally, you'll install Rails b3.
Install RVM (http://rvm.beginrescueend.com/rvm/install/):
bash < <( curl http://rvm.beginrescueend.com/releases/rvm-install-head )
Install the latest Ruby (http://rvm.beginrescueend.com/rubies/installing/):
rvm install ruby-head
You can check which versions you now have installed with:
rvm list
Set the latest version of Ruby as default (replace 'ruby-1.9.2-head' with desired version):
rvm ruby-1.9.2-head --default
Make sure things are up to day, then install the Rails beta:
gem update --system
gem install rails --pre
You may have to install some gem dependencies before Rails will install.