Most people these days, have a "flasher" style fish finder that they use for ice fishing, but when the season is over, they put that flasher away and don't think about it until the temps start dropping again the next year.
However, when asked, numbers of people will say that, “they don't feel like they know what they are looking at”, when they do use it. I have found that by using mine all season long, I am much more comfortable and also a better angler when the hard water season comes back around.
Most people have access to fish off of someone's dock and if you are one of these people, you are half way there. I am fortunate because, I work part time in a marina so I get to fish before work and at lunchtime.
I start out by walking along the dock, while holding the transducer of my Vexilar FLX28, just below the water’s surface and watch how it changes as I go. Paying close attention to when you are over the weeds, rocks or chains that hold the dock in place, so you can see how your flasher reads these objects.
By being able to see what is in the water under your transducer, you now have a very accurate account of what your flasher is telling you. Practice doing this while changing the settings on your unit to really get a good feel for its operation. Generally, there are at the very least, lots of bluegills or perch around so this really helps you to see how they show up on your graph.
Short rods work great for this style of fishing, because of the tight areas around the boats. Ice fishing rods work great too and are a lot of fun to use. Try using different ice fishing jigs and lures so that you can see how they show up on the screen and also to see which settings work best to seeing them. I also like to have my underwater camera with me to get a visual look at what my flasher is seeing and to see what kind of fish are down below.
Fishing this way during the warm weather definitely helps you get good at reading your electronics, which will help cut down on set up time when it's cold. Remember to be respectful when fishing off private docks and around people's boats and don't put those ice fishing tools away once the ice goes.