The arrow button is the manipulator. While it is pressed, you can manipulate objects on the object pane.
The other buttons with icons are node buttons. While one of them is pressed, clicking on the object pane creates a new object of the type specified by the node button.
Buttons with textual description are area buttons. While one of them is pressed, by pressing and dragging the mouse you can create an area of the specified type.
You can move nodes by clicking and dragging a node. When you drop a node onto anoter node, you will create an edge between these two nodes.
You can select multiple nodes either by clicking on them with the Control key pressed or by selecting by rectangular box.
You can drag and drop multiple selected nodes onto another node to create edges between the dropped nodes and the node dropped on.
Manipulation with areas is available by manipulating its border points. You can select and dragg a border point, resizing the area.
Right-clicking an object brings up a context-sensitive menu for the object.
The menu is divided into three categories: