Glue all the stones in, and allow to dry. (See technique sheet linked below, between glue and tools.) Be sure the siam (red) stone goes into the 1-loop setting.
Select 6 matching small (approx. 4mm) jump rings from the assortment. Attach the links and siam charm together in order. For best way to open and close loops, see Jump Ring Hint in Jewelry Basics 101 (PDF).
Select a large (8-10mm) jump ring to attach the rainbow pendant to the chain. This jump ring needs to be large enough to allow the pendant to move easily along the chain.
Attach clasp to chain - the clasp only fits over the ball portion, so if the end portion is a bar, snip it off with wire cutters.
2 feet #40-080-02-24-2 Brass Plated Steel Ball and Bar Chain By The Foot, 2.4mm
1 each #40-801-2-EA Raw Brass Ball Chain Clasp, 1.8-2.4mm
6 each #41-864-52-4 TierraCast Gold Plated Round Link with Stepped Bezel Setting and In-Line Loops
1 each #41-864-12-4 TierraCast Gold Plated Round Charm with Stepped Bezel Setting and In-Line Loop