Washington University is making ArcGIS Desktop available to all students, faculty, and staff for educational and research purposes. Most university computer labs have the ArcGIS Desktop (Advanced) application installed for your use. Students can obtain the ArcGIS Desktop Educational Edition for installation on their personal computer; see the ArcGIS Installation Guide For Students for details.
Faculty and staff who wish to run ArcGIS on a WU networked computer can install the ArcGIS Desktop suite, see the ArcGIS Installation Guide for Faculty & Staff for details. If you need to install ArcGIS on a remote or laptop computer, please contact Bill Winston or Mollie Webb to obtain a single use license.
QGIS is a free, community-developed, open-source desktop geographic information system application that can be installed on various operating systems. And it works on a Mac!
First: install these packages, etc., if you don't already have them running.
Next: install QGIS