How to double-shield a cable properly?
Ok I've been in the industry for years, and build signal power and video cables daily. Use tinned copper overbraid. Each shielded cable inside should have the shield exposed and stranded together so you can solder the shields to the overbraid. Then the answer lies in what type of connector you are using. I would typically unstrand the overbraid and lay it all the way around the back shell then heatshrink tubing over the overbraid and backshell. Heat very high, like 850-900, this will cause the 'tin' to flow and create a nice shielded cable. All signals shielded from one another and the entire cable shielded as well. Remember...do this on BOTH termination ends