Go to set up in the menu, select advanced mode. Set your down depth manually, never automatic. As you can see mine is set to 60' and the actual depth is 47.6'. You will have to hit your menu button once and adjust it as you fish different depths beyond your previous setting. Chart speed depends on how fast you're moving, but usually max or 75%, depends on how fast you want your screen to refresh. Sensitivity goes from 1 to 10, I usually set at about 7 or 8, but maximum is good if you don't get a lot of screen clutter. Set your sonar beam to 455hz for maximum coverage. I think I have covered the basics, just go out and play with the settings some. I still learn something almost every time out. I don't have the screen split with map/sonar, but that works well if you are trying to stay on a waypoint. The 597 is a decent unit for a compact 5" screen. Just let me know if you have any other questions.