The expression list is for more than just expressions. You can use the Add Item menu to add an expression, note, table, folder, or image to your graph. To start, click on the "plus sign" and then choose the type of item you'd like to add to your graph. An example of each is below:
Adding an Image
Add images to your graph to use as a template for your graph, add text labels, or for a little pop of extra color! To add an image to your graph, start by opening the Add Item menu and choose Image. Clicking and dragging the image into the expression list is also supported in many browsers.
To Move the image, click on the center point and drag the image to where you’d like to place it. To Resize the image, click and drag any one of the outer points surrounding the image. Dragging outwards to make the image larger and inwards to make it smaller.
Or, you can manually change the coordinate of the center point in the expression list. This will automatically move the image so that its center is at that new coordinate point. You can resize the image by adjusting the width and height. You can also adjust the angle or opacity of the image.
Click and long-holding the image icon will allow you to adjust the opacity and placement of the image.
Now that you know how to add an item, check out these articles!