This is a tip for making twisted power cables so that the inside of your cabs look neater if using separate cable, and I was also told that twisting speaker cables is good practice in cabs anyway...
This is the end result:-

You start off by cutting two lengths of your cable to be used for internal speaker wiring from two looms:-

Next attach one end of the wires into the chuck of your cordless drill/power driver and the other ends into the jaws of a bench vice (a G clamp will work on a bench if you don't have a vice)

Pull the cables tight and then operate the drill. The cables will twist together forming a tight length of paired cables that can be cut to size:-


Neat and tidy, tidy and neat
Dave