Oval chain
 Rosary chain
 3mm and 4mm rings
 A pendant
 A clasp and a clasp attachment

To start, cut the oval chain to 40cm. Adjust the length to your liking and body shape; here we made a choker necklace that falls on the top of the collarbones. 

Cut a piece of rosary chain keeping 17 beads. Be careful, for a nice fall, always keep an odd number of beads.

Then fold the oval chain in half to find the center. Then place the rosary chain at the edge of the oval chain, centering it. This way, you can determine the location of the rosary chain connection.

Lower the connection point by one link, so the rosary chain will fall below the oval chain.

You can now connect the rosary chain to the oval chain with 3mm rings.

Then place the pendant in the center of the oval chain with a 4mm ring.

To finish, attach the clasp and the connector to the ends of the oval chain with 4mm rings.

And there you go! Beautiful creation!