knit, purl?

[punta.livejournal.com]

I am very proud of my first real knitting project. I also learned how to purl recently, and this is the first time I have really used it.







As you can see, I am doing knit 5, purl 2, across the row.
I have not been able to find a simple scarf pattern that just uses knit and pur, so I can't figure out how it is usually dont. My stripes go vertically. But are they usually done horizontally? This would mean that I would do, for example, three rows of knit, 3 rows of purl. Please let me know what you all have found to be best. Thanks!