Once Ruby and RubyGems are installed on your computer you can go to a command prompt (located under accessories on your start menu or by typing cmd at the run command) and install the Rails gems by typing:

gem install rails

Rails is made up of a number of gems so this step will take a little time.

For this step to work you must be an administrative user on your computer.

Once this is complete, you should have rails installed and ready to go. You can test it out by going to the command prompt and typing:

rails new projectname

If rails is installed correctly, a new folder will be created called projectname.