Transforming existing data into graph formats and visualizing large graphs in a comprehensible way are two key areas of interest of information visualization. Addressing these issues requires new visualization approaches for large graphs that support users with graph construction and exploration. In addition, graph visualization is becoming more important for existing graph processing systems, which are often based on the property graph model. Therefore this paper presents concepts for visually constructing property graphs from data sources and a summary visualization for large property graphs. Furthermore, we introduce the concept of a graph construction time line that keeps track of changes and provides branching and merging, in a version control like fashion. Finally, we present a tool that visually guides users through the graph construction and exploration process.