What I want you to do is think of a book. Now, with no googling or shelf-searching, you need to draw it. You don't need to be an artist! Let's be real, the uglier it is, the funnier it is. Imaginary bonus points if you use MS Paint. Here's my example where I drew Grief is the Thing with Feathers by Max Porter.
Accuracy won't get you the win; just participation! Either post your creation in the comments or share it on social media with the hashtags #Readathon and #CoverFromMemory. The winner will be randomly chosen and will get to choose a prize from the prize page. Good luck!