Tie the central cord to the keyring with a few square knots. Leave plenty of cording to work with maybe 4 feet. You can cut the excess cording later.

Cut four 20 inch lengths of the cording to thread through the center of the drain and gather together at the top of the center cord by the ring.

Use thin dark wire to wrap the tops of the cording sections tightly around the central cord at the ring.

Drill a hole in the top and bottom of the sphere. Use a long toothpick or skewer and attach it to the bottom of the central cord and thread the sphere up to the central line.

Tie a couple of knots below the sphere to hold it in place midway alongside the chimes. Then slide the knob on the cord below the chime line and tie a couple of knots to finish off the central cord.

Cut your pipe into six pieces. I started with 10 inches and then decreased each next piece by 1/2 inch. 

Drill a hole through each pipe about 1/2 inch below the top. Use some painters tape or masking tape to help the drill bit stay in place.

Then string the pipes to the edge of the drain cover in equal distant holes using waxed twine. Hang the top from something to help you tie the pipes evenly around the drain.