To use Scheme from a shell, you need to add /cse/courses/misc_lang/axp/mit-scheme-7.3/bin to your path (in your .cshrc file). If you don't already have a path, then the line to add is set path = ($path /cse/courses/misc_lang/axp/mit-scheme-7.3/bin). Now you can type scheme at the shell to get the MIT Scheme interpreter.
To use Scheme from EMACS, you should add the following function to your .emacs file:
(defun mit-scheme () (interactive) (load "/cse/courses/misc_lang/axp/mit-scheme-7.3/lib/emacs/lisp/xscheme.el") (run-scheme "/cse/courses/misc_lang/axp/mit-scheme-7.3/bin/scheme"))
Now you can start MIT Scheme by typing Meta-x mit-scheme in EMACS.
Click on the Start button, and choose the Programs menu. From there, select the Server Apps menu, and finally select MIT Scheme 7.4.2. To use the Scheme interpreter as you would from a shell, choose the Runtime option. To use Scheme within Edwin, an editor which has essentially the same interface as EMACS, choose BchScheme.
You can download and install MIT Scheme 7.4.2 yourself. Here's the FTP directory and its README.