You should have the following pieces:
- Dish with 5/8" hole
- Bottom brass piece
- Top brass piece with loop
- Thin copper chain
Insert the bottom brass piece through the hole in the dish, from underneath.
Screw on the top brass piece and tighten, finger tight. You may need to hold the piece underneath so it doesn't spin.
Twist open the end link of thin copper chain, attach to the brass loop. You can easily do this with your fingers.
Close up the link.
Adjust the length, using as many links as needed to reach the bottom of your rain chain.