You start by avoiding tutorials, especially generic step by steps that will probably only teach you bad habits. Tutorials don't teach you anatomy which cartoons are ultimately based off of, or psychology that teaches you how far you can stretch and distort anatomy to have a decent looking, memorable character. Tutorials don't even teach you how to train your eye for proportions that can let you draw realistically, and IMO, probably the same eye needed to consistently draw cartoons consistently (I think)
Check out everything that you can get your hands on, don't just rely on one book or approach. Don't expect miracles, though, it takes a long time and a lot of practice to learn this stuff. If you could read a couple tutorials and be good, everybody in the world would be able to draw.
There's a bunch of theory to learn in cartooning. Look for books for animators, even if you're never going to do a lot of animation you will be using all the same principles, you just won't be making the character move.
"the one i'm reading is kinda complex"
Well, you have the rest of your life to figure it out and understand it.