Help with Colored Border

Hello all,
I’m trying to knit a baby blanket for a friend (from Debbie Bliss’ Baby Knits) and it is a simple seed stitch square, but it is edged by three rows of contrasting color. I’m doing it in green with a contrast edge of pink.
The directions are to cast on in the contrasting color, knit for three rows (making the bottom edge), then knit 3 contrast, knit the rest in the main color (107 stitches), then do the last 3 contrast, and then repeat this until the top, when I knit the entire row in contrast for three rows.
My problem is, the pattern says “When changing colors on the throw, twist yarns together on the wrong side to avoid holes.” So am I supposed to carry the pink across 107 stitches every row? I can’t exactly start a new color every time. It’s made more confusing by the fact that in her picture the “reverse” side of the blanked shows no signs of twisting yarns. Plus, I tried twisting the yarn every three stitches or so and it was still ugly on the reverse side.
Right now I’m debating placing the three contrast stitches on either side on needle holders and knitting them at the end, and sew them on to either side of the main blanket color.
Please help! I’ve done intarsia before, for goodness’ sake, and I’m totally stumped by this “simple” question. Thank you!

What you’re basically doing is intarsia I think. You need to twist the yarn so there won’t be a gap. Check these sites for some help on twisting the yarn.

Scroll about halfway down to see this one

Thank you! I guess what I knew how to do was “stranding”, not “intarsia.” I’ll try it this way. Thanks again!