Simply run:

# python install
In addition to installing Mathics, this will download the required Python packages sympy, mpmath, django, and pysqlite and install them in your Python site-packages directory (usually /usr/lib/python2.x/site-packages on Debian or /Library/Frameworks/Python.framework/Versions/2.x/lib/python2.x/site-packages on Mac OS X).

Two executable files will be created in a binary directory on your PATH (usually /usr/bin on Debian or /Library/Frameworks/Python.framework/Versions/2.x/bin on Mac OS X): mathics and mathicsserver.