These are called Cute as a Button Bookmakers. They are cheap, easy to make and are wonderful gifts!
All you need is
Pliers (which you won't need if you get the flat back buttons).
Step 1: Make a few fabric covered buttons.
These are size 45 or 1 1/8" buttons.
Step 2: If you use normal buttons you will need to take the loops off to make them flat. However you can buy flat back buttons and not have to worry about the loop.
Step 3: Add a dab of hot glue to the top of the large paperclip pad and place your fabric button on top of the glue.
Step 4: Let it cool and it's ready to use!