Help a beginning game hacker?

I've had 2 semesters of C++ but I feel unprepared to work on any interesting hacks. What I'd like to do is code simple things for BF3, like passive esp. I've played around in other games with Olly, finding and altering the asm to produce useful results. I've used WriteMemoryProcess (which I understand is not at all safe from PB) to do this in my own code. What I don't understand is where to go next.

I've found source for some hacks and read pages of discussions that don't mean anything to me. It's like everyone's talking about multiplication when I don't know addition. I don't need someone to hold my hand, just some direction. I've never worked on anything this complex. How do I learn to modify the game engine's behavior?

Learn the engine, learn the game. There's nothing like a universal hack that you can apply to every game. Every game is different and every game needs to be learned. To modify a game's engine/hack a game you need to study how it works. Read it's documentation (if any) break it open in your debugger and start digging through the code. Make a drawing/image of how the game works and think of ways to modify this behavior to suit your needs.

I know this sounds very generic, but then you ask a very broad and generic question