wire stripper, wire crimper, volt meter, 4x quick wire connectors, 4x male crimp connectors, 4x female crimp connectors, electrical tape
1. First, tape the halo and/or LED wires to the back of the headlights to keep them from tangling.
2. Keep the pairs in order by their color, e.g. black, black (ground) and Red, Red (positive). Note: positive and ground wires might not always be black and red.
3. Remove some of the plastic shielding at the end of the wires to expose enough copper wire, next twist the copper together to strengthen it.
4. Shove the twisted copper into a crimp connector; crimp the location where wire and the connector end overlaps, wrap with electrical tape to secure it.
5. The two extra wires in black and red will be helpful in making the halo/LED wires longer for easier installation. a) Remove shieldin, b) show copper, c) use the connectors, d) connect the positive and ground from the headlights.
6. Next step, turn the headlight switch inside the car to the [on] position.
7. Take the volt meter and connect the negative to the negative on the battery (please use extreme precaution when doing so).
8. The headlight harness usually will have  wires, generally red, black, green (headlights, ground, turn signal). Use the volt meter to test which wire will have power running through it (since the headlight is in the [on] position) which will be the headlight wire.
9. Use the quick connector to connect the extra wires (red) to the power wire on the harness and black to the ground. This will split the current coming from the harness. Crimp the connectors and use electrical tape to secure it.
10. Now connect the projector headlight halo wires and the harness from the car.
11. No wires should be left over unconnected.
12. The installation is now complete.