The chapter presents the methods in the information technology (IT) part of the decision support system (DSS). As a final stage in the DSS development, it integrates all the aforementioned decision support tools to build a user-friendly graphical user interface (GUI). Starting with the elaboration of the data management and ending in the implementation and testing phase, the chapter guides the reader toward system building. Although a little IT background will ease the reader to understand this chapter, a general reader may also benefit, as we provide the definition and further elaboration on the more technical parts. We highlight that future DSS projects must provide enough time to build specific machine learning to enable more sophisticated features, such as simulations of uncertainty effects.