LEARNING THE LAKE

Often when I say you have to, "learn the lake," it puzzles people and they say something like ....
"Okay, but how do you do that? You say the best way is to actually go out and cast it - but where to begin?”
Thats a fair question, and it deserves an explanation. So, lets open it up a little and unpack a method you can follow.

    Key Point: First, remember that 90% of the water is devoid of fish. So the goal is not to hit all the water, but to sift it methodically, and uncover the 10% of the water where the greatest number fish actually live. 

✅ With that in mind, get yourself a hydrographic map of the lake. If the lake doesn't have one, or you cant find one, you'll have to wing it. But you're still still not unarmed becasue you have your brain and your eyes, and you can think.
Stay with me and you'll see how to use all these tools to your advantage.

✅ Now with map in hand, look it over to determine the average depth of the lake, or the average depth of a smaller section area of a large lake. Sometimes this is marked right on the map, but if not, don't worry. Just look it over and get the general idea.
If theres no map, pretned to you have one. Now, do the same thing you would do with a map, using the shoreline slopes, points, grades and features as your guide.
This takes a little imagination and may not be obvious right away. But study the shoreline and mentally picture what it must be doing after it slopes into the water. 

✅ If the map reveals that the average depth is less than 20 feet, consider the lake shallow. With that knowledge, you can be pretty sure most of the larger fish will be concetrated around the deeper sections  of the lake.
No map? Dont sweat it right now. Keep reading.

✅ If the lake depth is 20 feet or more, on the average, consider it deep, and most of the action will occur around shallow-water breaklines. That is to say, along the depth changes that parallel the shore and lead from deep water to shallow.
If you have no map, you just discovered one of the best secrets you can have: Find the depth break lines and use them as your guide. 

✅ In the case of a shallow lake, or shallow section of a lake, read the wind and use it to set up a drift that carries you over the deeper spots, the breaklines and good-looking areas such as weed beds, reefs, sunken timber, channels, etc., and fan-cast the area.

✅ In the case of a deep lake, use your depth finder to navigate along a 10-foot breakline.
From that vantage point, cast to the shallow side of the break, then parallel to the break, and finally off the seaward side of the boat, straight out from the break..., gradually moving along on your electric motor.
Key Point: to do this casting, use lures that will "tip" along the bottom - not run in empty, fishless water.
You dont want the lures plowing down into the bottom, but staying within the 1 Foot Contact Zone 

Alright, let's imagine you don't have a hydrographic map. After reading through this, you should see that its still possible to work the lake in this general way. Usually, the shoreline will give you all the indications you need to know how the bottom is formed beyond it.
- For example, head to the nearest creek arm. Then, look at the shore and see how it slopes into the water. Its probably fairly shallow, and you can assume the bottom slopes down the same way beneath the water. From there, you'll hunt for the channel in the center - that's the deep section wherre the bigger fish spend most of their time. Hwo to find it? Use your depth finder to find the channel.
Points along the shore will extend out from shore towards the channel, too, and they will have depth breaks all the way around them. 
Coves and small inlets along the shore of this creek arm will have a, "front door," that leads to the channel, and you can work that, using the 10' break line along the front of the cove as your starting point.
- Next, you can parallel the shoreline along the 10' breakline, with your depth sounder, and you can work that by casting as described above.
- Lastly, you can join all the other guys banging the banks and mud line. Hey, you might get lucky there!

That's three separate options, and you've covered all the pertinent water in the area.
In doing it this methodical way, you will come to, "learn the lake"  - and almost always you'll come upon productive spots to mark for the next time you are on that BOW.  

Source: Jim Gamlin's Secret System To Catch Big Fish
MidWest Outdoors, Ltd., 1986
Taken from Facebook Group, "Structure Cafe"
Edits and additions, my own.