Peek Through Cowl

I have been wanting to make this cowl from Field Guide No. 6 for quite a while, and today was the day! No distractions–a whole afternoon to myself! However … I’m confused. The instructions say to make sure you don’t have “errant opposite-color floats in front of the work from either side.” OK. So here are part of the instructions from the set up row: “with A (keeping B in front), p3; with A and B held together, k3”. If B is in front of A while you are purling with A, when you knit the 2 colors together, there is a B float in front of A. Or, maybe, what am I not understanding? I’d love some guidance.