I had heard all kinds of advice about diving the Cooper before I did it, but I was unprepared for the dark. I only took a little light and it was not even close to enough. Its pitch black usually below 10 feet so take a good light. I use a tank mounted dive rite cannister 10w HID that clips to a hard hat. LED is also good. The brighter HID and LED are a big plus for black water, plus the longer burn times make them obvious choices over halogen.

Be prepared for less than 6 inches of vis, though I have had 8-10 feet before. Because of the low vis, you'll be diving solo. That's the way it is with all black water diving, but its worth mentioning because this is your first trip.

There can also be a lot of current, depending on where and when you dive so you should wear more weight than you did off Venice. I usually wear more than 20 pounds there with no wetsuit. Speaking of wetsuits, this time of year the water is pretty warm, so you won't need a heavy wetsuit. I wear jeans, a long sleeve shirt, and coveralls.

Don't clutter yourself with unnecessary gear. You won't need a snorkel, a tablet, or a camera. You will need a decent sized goodie bag. You should be prepared in case your duty is to transport a mastodon tooth back to the surface! You also should take a screwdriver. Its very handy to help pull yourself along the bottom against the current.

Find a way to clip everything to yourself, especially your goodie bag.

That's all I can think of right now. I'm sure somebody else will remember something I forgot.  Stay safe and have a great dive!