The interface and menus should be pretty self-explanatory, but here are some tips to get you started:
* Click on a relation to select it.
* You can CTRL + click to select multiple relations.
* Drag the relations to move them around in the window.
* Right-click on different areas to access context menus with some helpful actions.
* When exporting the model to an image, be sure to add the desired image file extension (`.png`, `.jpg`, `.bmp`, etc.), or the application will default to `.png`.