Firstly, install the Apple Developer Tools (Xcode) found on the Mac OS X installation disk or downloaded from the Apple Developer Connection downloads page.
Leopard
On Leopard, installing the Developer Tools is all that is required to use Ruby, RubyGems and Rails. You should update your copy of Rails with the following commands, but apart from that, you’re ready to go.
sudo gem update --system
sudo gem install rails
sudo gem update rake
sudo gem update sqlite3-ruby
Installing with MacPorts
You may wish to use MacPorts to install Rails if you are using Tiger or Panther. Also, the MacPorts installation offers more flexibility with adding and updating additional packages, so is also suitable for installing on Leopard.
- Download and install from the MacPorts install page. MacPorts can be installed with a .dmg image using a familiar step-by-step installer.
- Open the Terminal application and type the following command, followed by the return key. It will most likely prompt you to enter your password.
sudo port install ruby rb-rubygems - Installing Rails using RubyGems is a simple command:
sudo gem install rails
That’s it! Now you’re ready to create new Rails applications with the rails command.