Start with either an A4 sheet of card or a 12" square (this is a 12" square)
Score down the centre
turn card top to side and score in the centre of the card - then in the centre of each side to create 4 equal sections
fold along all of the crease lines really well to create the book pages
you will be pushing out the centre crease of the gap you made
add some double sided tape on the sides indicated - you can place the tape along the sides/edges of the panels for a better stick - I just wanted to show you the panels you need to add the tape to
fold along the centre line and secure the book in half
then secure the centre pages to create a star shape
Fold your star into the completed book shape - give the card a good old 'wriggle' to make the pages sit well together
Now you can decorate you r book as you wish - the smaller one is made from an A4 sheet of card.
PS - I do trim the page edges to neaten them if the centre fold sticks out a bit.
Dead easy - love it!