You will need a piece of cardboard, clothespins, a pair of scissors and glue.
Take a piece of cardboard and draw a circle having a 5-6 cm radius on it.
Cut out the circle.
You can use the cardboard circle as it is, or can cover it with a coloured sheet of your choice.
After your circle is ready, stick one side of the movable part of a clothespin across the border of the cardboard circle in such a way that the other part is free to be pressed for opening the clip.
Once all the clothespins are glued around the circle, clip your pictures on them.