The approach
Start with the right question.
Compare bottom, cover, depth and retrieve speed before changing every part of your setup.
In practice
Make it useful on the water.
Change one variable per outing so the result tells you something useful.
Keep learning
Connect the dots.
Use this guide as a starting point, then compare it with the water you're fishing, the tackle you're using, and your own observations. Good fishing knowledge grows through real practice.