The relay looks fine, 4-pin relays are used to turn a single item on and off and that's what you need here. 5-pin relays are to switch one item on when another is off, then flip that over (so that the first light switches off and the second switches on, say).
I got that system with my lightbar and threw it away because it doesn't allow for activation on high beam which is the legal way to do it. I even threw the relay socket away. What you need is this:
Connect one wire from the battery directly to a fuse. Connect the other side of that fuse to pin 30 of a relay (via a socket is fine). That's the input power done.
Connect one wire from the high beam wire as Bods has described to pin 85 of the relay. This is the trigger.
Connect a wire to an earth source under the dash to a switch placed somewhere on the dash board. Connect the other side of this switch to a wire that you run out of the cabin and connect it to pin 86 of the relay. This is what allows the relay to turn on and off.
Next to last - connect pin 87 of the relay to the RED wire of the light bar. No need for a fuse here.
Lastly, connect a wire directly from battery negative to the black wire of the light bar.
That's it. Operation is simple: with the switch inside in the "off" position you can flick high beam as much as you like the light bar won't come on. Now, with high beam ON, flick the driving lights switch inside - the light bar comes on. Turn high beam off - the light bar turns off. That's the legal way to do it.