"Black" as a color code is traditionally NEGATIVE, and red positive.You don't have to, but it's a good idea. Just run a second pair alongside the first and connect them in the same spots. Tape them together an inch or so from the terminals so any movement they'll do together. You can use any tape, but I prefer electrical. Better yet, use shrink wrap tubing. For either tape or tubing I recommend using black for positive and maybe red or white for negative. It just makes they easier to identify.
I've been playing with electronics most of my life.
John Kuthe...