All professional programmers know that they never program in a vacuum. They write their code as if they were PairProgramming, even when they aren't.
They know that eventually some poor slob will have to expand, enhance, modify, or (heaven forbid) fix their quick hack or elegant solution.
You may find it helpful to imagine someone looking over your shoulder while you write. Perhaps a beloved professor, friend, or even EdsgerDijkstra.
Comments are for the next guy, who many times, is you.
Good style is for the next guy.
Consistency is for the next guy.
Names (short or long) are for the next guy.
Common sense, well, nobody's got enough—just hope for the best.
Making minimally intrusive fixes are for the next guy.
Working with TheNextGuy in mind is an application of the GoldenRule.
And you may be TheNextGuy in a few months.