As pointed out by pfred2, if your project is very sensitive to wire crosstalk, use only twisted pairs (two strands) and not more, like I use to demonstrate in this instructable.
You will need:
Insulated wires (This will not work with bare wires!)
Wire cutters or scissors
Drill with adjustable chuck (ideally electric, but you could do this with one of the hand-crank ones too)
Step 1: Step 1: Cut
Note that the thicknesses of the wires don't matter, but the closer the diameters are to each other, the cleaner the wrap will come out.