Output Image
First, use the TETRAD GUI (available from the bottom of the CCD Tools page) to make a graph. In the GUI, click on the "Graph" button to make a graph box in the work area. Double-click on that box, select "Graph", then use the tools on the left side of the dialog box to create a graph. From the File menu, select Save...>XML to export the graph as an XML file.
Use the "Browse..." button below to import the xml file that was exported from TETRAD. This will load the graph data into the graph area. Drag the nodes around until you are satisfied with their position. Click on nodes or edges to invert their color in order to highlight them. Right click on the nodes to open a menu which can be used to convert it into a latent variable. Then click on the "Output PNG" button to generate the image which will appear below the button. Right click on the image and select "Save Image As...". The "Output JSON" button is used to generate the code that is used to represent the graph in CTAT tutors.