Did you get the S10 specific 3CS kit? That one is the most straight-forward and I've installed that. I don't have pics at the moment. I've also done a 3CS universal kit on a different motorbike and made my own relay kit for an ATV before I knew the magic of 3CS.
Assuming you have the S10 kit, the major benefit is that you can plug right into the auxiliary connector. If you don't have the S10-specific kit, others will need to chime in on good connection options. After that, you need to hook up the two main cables to their respective battery terminals. The specific circuit connectors require crimping or soldering whatever you are connecting into the "load side" plug. I can't recall if the 3CS kit has the relay side plugs already in place. If not, then those need to be crimped or soldered on. I've used their sealed system and it's a little tricky to get the plug seals set, but I've had success using an awl or very small screwdriver to push the plug seal in place. I'm a crimper and haven't had issues so far. It does take some patience and care to crimp the 3CS plug bits to whatever wire you are using, but it works. The pieces of the plug need to be on the wire before you crimp so that you can then pull the plug housing and plug seal over the electrical connector portion of the plug (I made the error of not doing that once).
On the S10, you need to figure out where you want to put the 3CS relay and fuses. I managed to cram mine behind the cowl and next to the battery. I used the rubber battery tie-down to hold the fuse block. Not pretty, but it's behind a cowl and I just have to be mindful of the wires when I pull the cowl off or put it on. The wires and such will fit - i just tie them up so the relay and wires don't flop too much. And don't forget to make sure there are fuses in the fuse block for the circuits you are using. I've forgotten that step and the past and thought I'd biffed the wiring, when it was just a missing fuse. Derp.
Hope this helps a little. I'm sure there are others who can contribute more and better. If you aren't comfortable with wiring and connecting things, it might be best to get some assistance, at least for the first circuit you do.
Eville Rich
2016 S10
2015 WR250R