Jan, it's slowly becoming a bit more clear....
Jan, I can't thank you enough for your help! I realized that some confusion was generated by my referring to the wrong pattern name. I'm actually wanting to do the one called "Easiest Baby Blanket" from the longer list you sent me; it was one I had actually looked at the other night. THAT one does call for circular needles, as well as alternation between knit and purl stitches.
Anyway, that being said, I think I'm getting more of an idea how to work it. What you are saying is that I will basically be using the circular needles as if it were one really long straight needle. I'll work off of the left onto the right, then turn the work around and knit my way back for garter stitch, or purl my way back for stockinette stitch. Is that right?
In addition, I think what I will do is get a yarn that is a bit thicker/fuzzier, so that I won't have to worry about doubling the strand. For future reference, though, when doing a double strand, would I just get two skeins of the same yarn and pull from them both/work them together at the same time? Or is there a better way of doing that?
Again, I'm really encouraged by your help and support. I'm looking forward to getting started.