Always code as if the person who ends up maintaining your code is a violent psychopath who knows where you live.

Without requirements or design, programming is the art of adding bugs to an empty text file. (Louis Srygley)

A good programmer is someone who always looks both ways before crossing a one-way street. (Doug Linder)

Any fool can write code that a computer can understand. Good programmers write code that humans can understand (Martin Fowler)