Simply, download the package, decompress it and

• create the ".depend" file
> .depend
• calculate dependeces among files
make depend
• compile it (the result code is not interpreted)
make

You need to have the following tool:

• Ocaml and its standard library
• extlib (link here), an extension library for Ocaml
• ocamlfind (also named findlib), a tool used to search and import extra libraries
• make

This version is very simple. You have a main menu, where you can do three kind of actions.

• Insert a new expression
• See all the inserted expressions
• Do a reduction (you'll have to choose the expression from the inserted list)