Red = power
Black = ground
Splice the left headlight black wires together and put them to a ground (bolt). You may need to splice in extra length of wire. Next, do the same with the right headlight. No need to splice the left and right headlight grounds together (4 wires all attached).
Now for power, here's what I would do. If you want the halo and R8 LEDs to all come on together, then splice the red wires together at each headlight and connect them to your running lights (read below). If you want to control them separate, you need to have two switches and splice the matching left/right headlight red wires together. Little more work, but it gives you some different options.
So now that you have the red wires spliced together between headlights, you need to decide how you want them to turn on. Do you want a separate toggle switch or do you want your headlight switch to turn them on? Most often, people want them on with the 1st click of the headlight switch (running lights). It's easier to do it this way because the power is right there at the headlight. Turn your headlight switch to the first click, see what comes on, then splice your red wires to that bulbs power wire (you'll do this twice. One set of spliced red wires on the left and one set on the right).
If you want a switch in your cabin, just get a simple on/off switch. Run a power wire (with fuse) off your battery and into your cabin, then run your extended red wire off the halo/LED (you'll either have one wire to run because you've spliced them all together or two wires to run because you want a switch for halo and a switch for R8) into your cabin. Now you have two wires going into your car. One has power off the battery, the other is where you want power to go (headlights). Connect them to your switch, and boom goes the dynamite.
Make sense? Super easy to do.
Though I have to honest and tell you that aftermarket headlights suck. OEM's are better and cleaner. I've never been a fan of DEPO's (or what ever knock off brands are out there these days). They just give you that cheap feel and devalue Civic's as a whole. Just my .02
