It isn't difficult, compared to say coding a cheat for a game such as BF2 but you're still going to need to understand a few fundamental things to get going. Firstly you're going to have to either concentrate on the memory hacking/debugging aspect of it all, or focus on learning some basic programming to wrap it into a nice little package.
I suppose someone could come along and just give you all the answers and show you how to do it, but that will only lead to you releasing it and generally causing a mess for the forum overlords. I guess if you took some time and went about how to do it properly, you'd take a greater interest in releasing something to the public as well for yourself.
If you however get an S2 license I'll consider giving you
some of my source code related to LFS stuff, as well as a few other pointers on how to get going - If you're intrested that is