This is a (deprecated) guide to installing Ruby using RVM. I wrote it as a guide to get myself set up quickly in a development environment, but you should just see the RVM docs.
curl -O http://ftp.ruby-lang.org/pub/ruby/1.9/ruby-1.9.3-p194.tar.gz tar -xvf ruby-1.9.3-p194.tar.gz cd ruby-1.9.3-p194
Check Ruby Download for a more recent version than p194.
Dependencies can be resolved manually by doing
./configure && make and checking to see what Ruby complains about in the compiler output. A much easier way would be to simply install RVM and run
sudo yum install ncurses ncurses-devel gdbm-devel libffi-devel openssl-devel libyaml libyaml-devel readline-devel tk tk-devel patch bison autoconf automake sudo yum install git gcc-c++ readline zlib zlib-devel make bzip2 libtool
The first set of packages are the requirements I divined from configuration and compiler output, before learning about
rvm requirements. The second set are the remaining suggested requirements for my platform, which were either already installed or ultimately unnecessary.
./configure make sudo make install
curl https://raw.github.com/wayneeseguin/rvm/master/binscripts/rvm-installer | bash -s stable
rvm install ruby-1.9.3-head rvm use ruby-1.9.3-head --default
rvm implode whereis ruby rm -rf (files/directories listed in whereis ruby)