Print out your pictures, 9 to a sheet. They should be 2.5 x 3.5", will shrink to about half size. Cut out and round the corners. You can do it with scissors too. Punch holes , two on each side. If you want to join with elastic do all same way. For a clasp, punch one hole on clasp ends.
Use a pencil or chopstick to gently hold plastic when using heat gun.