use jewelery mode
3-4 discrimination bars dry sand 1-4 in wet sand
If you get a weak signal try to swing the coil faster over the target. That improves target ID and depth
If you get a coin signal and it seems to cover too much ground , it probably is a can. And you can lift the coil about 6" and if you still hear it, it is probably a can. If you can't hear it then it is most likely a coin
If you turn off the power, wait a few seconds and turn it on again, it re-tunes itself to the local conditions where you are standing. ( it seems to work)