The single biggest favor you can do for yourself is to write simple, obvious, documented code. Put it in callable subroutines, modules, or "daemons," and use it over and over.
The two biggest jerks that I have to work with on a daily basis are both me.
The first one is me last year, who considered the piece of code that I'm looking at now to be so obvious that it didn't require annotation.
The second one is me next year, who is such a dummy that he wants me to put notes on everything!
:)