I've just started jigging around bouys and have caught a shibi with the diamond jig. I have no clue about what depth to jig, I just let out half the spool and started jigging it back up. Then down again. Then up. Then down. Trying all kinds of different ways. Must have just been a hungry fish. Good to have the right kind of equipment. A lighter rod will not give the lure good action and you'll be wasting a lot of energy.
Try using an assist hook with your jigs. Williamson benthos or abyss jigs are good quick jigs that get deep fast, they are reasonly priced too. Go as deep as you can and work the jig all the way up through the water column. look up videos on youtube for shimano butterfly jigs to see the how to retrieve the jig. You got got braid or mono? Spinning reel?
you can use any type of jig you want. this is the way I was taught, the important thing is to mark you your main line so you know how many fathoms of line are out, and watch your recorder. make a pass or two if can and mark the depth the fish are hanging at, then let out your line I usually go a couple of fathoms past the mark.
As for lure type I have had luck with diamond jigs aswell as plastic baits just go out with a wide assortment (unless you got inside info...) and try em out