You can save your drawing in a file by pressing 'Save Drawing'. Load it back in later with 'Load
Drawing'. If you already have a drawing in Cellular and you load in a new one, you'll be given the option
of deleting the old drawing or merging it with the new one. You may also find links to Cellular drawings
on NRICH which you can download and use. Cellular drawings are saved as XML files with the xml extension.