Magnetic properties are becoming increasingly important, especially with the advent of new technologies such as data storage, spintronics, and magnetic random access memory (MRAM). These technologies all benefit from the ability to characterize and optimize magnetic materials, which can be accomplished through the implementation of the magneto-optical Kerr effect (MOKE). This probing technique is described in detail along with the results of a self-built, longitudinal MOKE (L-MOKE) experiment that is used to determine the Kerr angle and ellipticity for the Heusler compound Fe2MnSn. The results from L-MOKE are combined with raw X-ray Diffraction (XRD) data in order to develop a complete picture of the material by connecting the Kerr response with the crystal structure. Trends in the crystal structure and magnetic properties of Fe2MnSn are developed and analyzed in order to isolate crystallographic directions that are primarily responsible for unique magnetic properties such as perpendicular magnetic anisotropy. Complementary techniques are also introduced to further the capabilities from a single geometry MOKE experiment to a compound experiment using all three geometries of MOKE with the ability to probe micro-structures, determine magneto-optical parameters, and create magnetic domain images.