Firstly,determine how slack you want the double U-shape to be and hold it together with safety pins.

Then,pin the safety pins into alternate holes on the chain.

Using ribbons or strings,thread it through the 2 safety pins(used to determine U-shape).

This way,you can wear it long or short,even as a choker. =)

Plus,there will be a beautiful bow(or whatever shape you want to tie it)at the back.

Personally,I think wide black ribbon will be really elegant.Too bad I don't have it at the moment.

As my chain is long and I had no idea how to cut it at home.

I curl it around the safety pins and secure in place with samll jump rings.(As shown in red)

Another way is to join the extra two to form a 3rd U-shape with the help of a small jump ring as well.(As shown in blue)