MS Visio is a popular application that lets you create a wide range of diagrams such as flowcharts, data flow diagrams, business process models and etc. VSDX is the file format that MS Visio uses to store the diagrams. In order to automate VSDX manipulation, this article provides you a basic tutorial of how to create VSDX diagrams from scratch in C#. Furthermore, it covers how to insert pages, shapes, and text in the VSDX diagrams from within .NET applications.