Strip the protective coating from the ends of each of the wires to be spliced using wire strippers, exposing two inches of bare wire. If several wires are bundled together, use a utility knife to remove the sheathing from the wires carefully so 4 inches of loose wire extends from the sheathing.
Slip an 8-inch piece of heat shrink over the end of one wire bundle, and slide it up the wire and out of the way. Slip a 3-inch piece of smaller heat shrink over one wire of each pair you plan to splice.
Cross the bare ends of a pair of wires perpendicular to each other with approximately equal amounts of bare wire (for example, 1 inch) on either side of the cross. Wrap one wire clockwise around the base of the other, then wrap the second wire clockwise around the base of the first. Gently tug the wires apart to tighten the connection.
Plug in a soldering iron, and allow it to heat for five to 10 minutes. Touch a soldering iron to the twist of the wire splice, with the tip of the iron touching both wires. Remove the soldering iron after 30 seconds to one minute, and immediately touch the solder to the twisted wires; the solder should melt instantly into the grooves of the splice. Allow the splice to cool for one minute.
Coat the soldered splice with liquid vinyl: Paint the vinyl onto the splice with the supplied brush cap. Allow the vinyl to dry according to the manufacturer's recommendations.
Slide the small heat shrink sleeve down the wire over the vinyl-coated, soldered splice. Heat the sleeve with a heat gun until it shrinks to fit the wire; hold the heat gun a few inches from the wire, and move it slowly back and forth to heat the sleeve.
Repeat the twisting, soldering, vinyl coating and heat shrinking process until you have connected all the wires. Slide the larger heat shrink sleeve down the wire bundle over the spliced wires, and heat the sleeve to seal it.
Secure the wires on each side of the splice with cable clamps: Screw the cable clamps in place with screws and a screwdriver to prevent the spliced wires from moving and breaking.
