Bottle caps, Woollen thread, big needle and beads for decoration.
Make a hole in the centre of the cap . Pass the needle and thread from inside the cap and and then pass the needle through the other end of thread and form a pattern to cover the entire cap.
Use contrasting colours of threads.
After deciding a pattern arrange the caps in that pattern and join using thread.
Fix beads in the centre and hang from sides.
Your wall hanging is ready.