You need to try different things. You can try dropping it down and jigging it at different levels until you find where the squid are in the water column. I jig with a short up stroke (say 10-12") then let the jig settle. Wait a few seconds then jig again. Or you can use a series of quick short jigs followed by a pause. Either way, after the wait make a slow rise. If you feel any weight "set" the jig and reel in the squid. Sometimes the squid will hit as you slowly raise the jig.
Another approach is to cast out to the shadow line, engage as soon as the jig hits water and let the jig angle back to you. Maybe give a little twitch along the way. Watch the line for any slack should could indicate a squid has hit.
There are no set ways to fish for squid. Squid in different locations seem to sometimes want different ways of jigging. Also, jigs like the Yozuri are worked differently than tear drop or "Pen Cap" jigs. Ideally you can fish around others who know the area and you'll see what they're doing.
Unhooking a squid isn't a problem. Squid jig hooks are more like a crown of prongs - no barbs. Just turn the jig upside-down and the squid should just fall off. Typically the squid will "ink you" when it first comes out of the water so don't wear good clothes fishing!
I'll leave the cleaning answer to someone more experienced - I use them for bait.
Good luck!
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