Ruben...
If you can afford it, I highly recommend Tom's Beach DVD. He uses a CZ in the biggest part of the video and explains about anything you need to know about beach hunting. I have a CZ6a that Tom converted to CZ3d and I did a very simple mod so that it has 4 tones like your CZ3d. If you will be hunting mostly in wet salty sand or shallow salt water, you will set the detector in Salt mode. Ground balance usually makes no difference in this mode, only when you'll be in the dry sand and in Enhanced mode.
When at the beach, I hunt the wet sand after the tide has gone out. That's where the swimmers were swimming at High tide, and lose their jewery. Of course they swim at low tide and lose jewery there also, but the CZ3d is not water proof, so I only go in sometimes to about half way to my knees into the water, if I go at all. I love to hunt by sounds only with the 3d. You only have 4 tones to remember and you can quickly learn what type of metal you have found without looking at the meter all the time. I will look at the meter to determine depth, but that's about all. I think the most important thing, other than learning to read the beach, is learning to recover your targets quickly. If you diddly dalley around (technical term) with each target, you will loose a lot of opertunities of finding much more targets with chances of some of them being very good. I use what some call a ladies shovel. It's a bit smaller than a full size shovel and has a bit smaller diameter handle. The handle is still long, and I can quickly leverage it with my thigh/knee to get the sand up while keeping my detector in the other hand.
Pinpoint, shovel the sand over to the side, check to see if I have the target out of the hole, kick the sand with my foot, if I don't see the target, detect the leveled sand, smooth the sand again and you'll probably see the target. Pick it up and fill the hole with your foot, keep moving to the next target. You can cover a LOT of beach this way and find many more targets. The more targets you find, the better chances of getting a real keeper.
Others will help out here. Good guys. LOTS of info here. Keep going thru the post until you see something that you think might be of help and read.
Good luck!