Lots and lots of comment.

When I was a programming novice, I didn't comment much.
When I was a programming acolyte, I commented a lot.
Now I am a programming master, and I try to minize the comments in my programs.

Why, you may ask. Doesn't more comments make it easier to understand what code does? Yes, it does - however, comments don't solve the cause. Comments fix the symptoms. Comments are used when the program isn't clear. If you write clearer programs, you need less comments.

It's like taking painkillers. They cause the headache to go away, but it's better to stop banging your head.