And yes I know, if I had spent the time taken to make a bookmark actually reading the book I would probably have finished the book anyway. But that's just no fun.
What you need:
Scraps of fabric
sewing machine and thread
should this not take your fancy.
Cut 2 pieces of card the same size. On one piece of card cut out your design.
Glue scrap pieces of fabric on the uncut piece of card.
Put the cards together wrong sides facing.
These are some other bookmarks I came across here, here