(1) Make an environment variable called RTS and add it to your .profile or .cshrc depending on whether use ksh or csh. I am giving the csh version here. ksh/bash/zsh/esh users change it appropriately.
setenv RTS ~/rts
setenv PATH $PATH:$RTS/bin
now do a 'source .cshrc'.
(2) type 'setup'.
Now you are ready to use RIT.
It would be great, if things really work on all the systems the way we specified here. However, there are likely to be some problems depending on which version of 'dvips' you use and how your system administrator configured your TeX. TeX has very minimal platform dependency but a great deal of site dependency. A lot of problems come down to not finding a directory or a file.
'rit' is a shellscipt. It sets environment variables and runs the programs 'tltr', 'latex', 'dvips'. Try running each of these steps individually. If the problem is with 'dvips' try
dvips -d23and it will show you all the directories it is trying. Basically it has to find .dvipsrc in your $HOME and $RTS/ps and $RTS/fonts/vf.
For more information on dvips read Frequently Asked Questions
Enjoy!