Online cabling help (for Dummies, no less!)

I finished the first 8 rows of the DNA scarf, in seed stitch. I am really glad now that I knit that k1 p2 ribbed scarf out of S'n'B, since it made doing the seed stitch a lot easier -- at first I had trouble telling the knits from the purls, since the bumps move around more! For some reason I thought the borders were much larger, but now it is on to the dual challenge of reading a pattern and cabling. Or perhaps I should say triple challenge, since I've just realized that I've never knit in stockinette or any other non-reversible stitch, and I have a sneaking suspicion grading to horrible fear that my tension will be off and it will look crappy. Well, I suppose I shouldn't go borrowing trouble.