I mader my cover off cerealbox cardboard. It's something everybody has in there home and easily bendable and durable. If you however choose to have a papercover skip this step and go to 6. Or if you want a hard cover choose your cardboard accordingly. I chose cerealbox because it was laying around here and I needed something bendable for on the train.
So first cut open your cardboardbox through the sides since we won't need those. Then spread it on the table. Now flip the box so the printed side is up. Now put your stapled together papers on the carboard and trace the shape with a pen. It doesn't need to be exact as long as it is straight so use a ruler. I made mine a few milimeters larger then the paper. Repeat this step for the backcover.
Use those lines to cut out your shape using scissors.
Now you have your two covers it's time to continue to "attaching the cover!"
Design notes: in this instructable I will use the unprinted back of the cardboard to make a drawing for my cover (more info on that later). Ofcourse there are other options. For example you can print your own image and paste it on the cardboard. You can leave the cerealbox print on it for that funny sight when it looks like your drawing inside a cerealbox. There are hunderds of other options so go nuts :D