Having your signal wires in a different sheath from the motor wires can help since the motors are a big source of spikes. In theory, twisting the motor wires could help also. If you do twist the motor wires together, it will work best if the pair used for each phase of the stepper motor windings is done together as a pair. That will improve the motor functionality for each phase. But unless you have very long wires or very large motor currents, that isn't much of a factor.
Also, keep in mind the motor wires are 'high current', so the air flow around them helps in cooling the wires, but if you use heavier gauge wire, that's not important. This only becomes a factor with high current motors and lighter weight wires combine with long print times, so most people can ignore it.
Also, keep in mind the motor wires are 'high current', so the air flow around them helps in cooling the wires, but if you use heavier gauge wire, that's not important. This only becomes a factor with high current motors and lighter weight wires combine with long print times, so most people can ignore it.