Use spaces, not tabs, to indent for print-outs.
Of course this all depends on the problem. The initial assignments are very simple, and fundamentally easy to understand. There really isn't more than one way to approach them. However as the semester progresses, you should find yourself spending more and more time on design, debugging, testing, and documentation, and relatively less on mere coding.
Later homeworks will be more complex, and thus count more heavily toward your final grade.
