You probably don't need instructions for this one but just incase...
Instructions:
Cut two equal rectangles of material (large enough to fit a large book in). Pin rectangles together, print facing in, sewing three sides together. Fold fourth side twice, iron flat and then sew neatly. Attach two equal lengths of bias binding at the top, 6cm from each side of the bag and at least 2cm deep or equal to the hem. Sew a square to secure in place and for extra strength. Turn inside out.